title: John Allen Chau

text: Despite efforts by Indian authorities, which involved a tense encounter with the tribe, Chau's body was not recovered. Indian officials made several attempts to recover the body but eventually abandoned those efforts. An anthropologist involved in the case told "The Guardian" that the risk of a dangerous clash between investigators and the islanders was too great to justify any further attempts. A murder case was opened following his death.


title: John Allen Chau

text: Chau was criticized by Survival International among others for visiting the island despite the possibility of introducing pathogens to the native Sentinelese, to whom it could have been deadly since it was likely that the natives had not been previously exposed to diseases from outside the island. All Nations, the evangelical organization that trained Chau, was criticized on social media for describing Chau as a martyr while expressing condolences for Chau's death. Chau's father also blamed his son's death on the missionary community for inculcating an extreme Christian vision within Chau.


title: John Allen Chau

text: In response to Chau's death, M. Sasikumar of the Maulana Abul Kalam Azad Institute of Asian Studies questioned the legal charge of murder and what he perceived as a romanticized version of the incident in the media. He wrote that the incident should instead serve as a warning that the "eyes-only" policy with regard to the Sentinelese needs to be more strictly enforced, and include the local fishermen in order to prevent a repetition.


title: John Allen Chau

text: Michael Schönhuth, Professor for Cultural Anthropology at the University of Trier, Germany, found the media response to Chau's killing of cultural interest: He wrote that the narratives that emerged were part of a larger discussion regarding the proper relationship between the modern world and the remaining isolated indigenous peoples.


title: John Allen Chau

text: Schönhuth wrote that the online presence of the Evangelical missionaries whose numbers had grown over the preceding twenty years, and in which Chau was an active participant, presented a narrative in which they were bringing civilization to a primitive people, and that the likelihood of missionaries being killed was not a deterrent, but an affirmation of the need for the "uncontacted people" to be rescued from a savage existence.


title: John Allen Chau

text: Schönhuth faulted the media for playing into this narrative, ignoring the history of exploitation of the people in the region, which presented an alternative narrative in which the killing of Chau was self-defense. Schönhuth suggested that the media hype must be reinterpreted to allow for such alternatives to be understood.


title: Chlorine

text: Chlorine is a chemical element with the symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Pauling scale, behind only oxygen and fluorine.


title: Chlorine

text: Chlorine played an important role in the experiments conducted by medieval alchemists, which commonly involved the heating of chloride salts like ammonium chloride (sal ammoniac) and sodium chloride (common salt), producing various chemical substances containing chlorine such as hydrogen chloride, mercury(II) chloride (corrosive sublimate), and hydrochloric acid (in the form of ). However, the nature of free chlorine gas as a separate substance was only recognised around 1630 by Jan Baptist van Helmont. Carl Wilhelm Scheele wrote a description of chlorine gas in 1774, supposing it to be an oxide of a new element. In 1809, chemists suggested that the gas might be a pure element, and this was confirmed by Sir Humphry Davy in 1810, who named it after the Ancient Greek (, "pale green") because of its colour.


title: Chlorine

text: Because of its great reactivity, all chlorine in the Earth's crust is in the form of ionic chloride compounds, which includes table salt. It is the second-most abundant halogen (after fluorine) and twenty-first most abundant chemical element in Earth's crust. These crustal deposits are nevertheless dwarfed by the huge reserves of chloride in seawater.


title: Chlorine

text: Elemental chlorine is commercially produced from brine by electrolysis, predominantly in the chlor-alkali process. The high oxidising potential of elemental chlorine led to the development of commercial bleaches and disinfectants, and a reagent for many processes in the chemical industry. Chlorine is used in the manufacture of a wide range of consumer products, about two-thirds of them organic chemicals such as polyvinyl chloride (PVC), many intermediates for the production of plastics, and other end products which do not contain the element. As a common disinfectant, elemental chlorine and chlorine-generating compounds are used more directly in swimming pools to keep them sanitary. Elemental chlorine at high concentration is extremely dangerous, and poisonous to most living organisms. As a chemical warfare agent, chlorine was first used in World War I as a poison gas weapon.


title: Chlorine

text: In the form of chloride ions, chlorine is necessary to all known species of life. Other types of chlorine compounds are rare in living organisms, and artificially produced chlorinated organics range from inert to toxic. In the upper atmosphere, chlorine-containing organic molecules such as chlorofluorocarbons have been implicated in ozone depletion. Small quantities of elemental chlorine are generated by oxidation of chloride ions in neutrophils as part of an immune system response against bacteria.


title: Chlorine

text: The most common compound of chlorine, sodium chloride, has been known since ancient times; archaeologists have found evidence that rock salt was used as early as 3000 BC and brine as early as 6000 BC.


title: Chlorine

text: Around 900, the authors of the Arabic writings attributed to Jabir ibn Hayyan (Latin: Geber) and the Persian physician and alchemist Abu Bakr al-Razi ( 865–925, Latin: Rhazes) were experimenting with sal ammoniac (ammonium chloride), which when it was distilled together with vitriol (hydrated sulfates of various metals) produced hydrogen chloride. However, it appears that in these early experiments with chloride salts, the gaseous products were discarded, and hydrogen chloride may have been produced many times before it was discovered that it can be put to chemical use. One of the first such uses was the synthesis of mercury(II) chloride (corrosive sublimate), whose production from the heating of mercury either with alum and ammonium chloride or with vitriol and sodium chloride was first described in the "De aluminibus et salibus" ("On Alums and Salts", an eleventh- or twelfth century Arabic text falsely attributed to Abu Bakr al-Razi and translated into Latin in the second half of the twelfth century by Gerard of Cremona, 1144–1187). Another important development was the discovery by pseudo-Geber (in the "De inventione veritatis", "On the Discovery of Truth", after c. 1300) that by adding ammonium chloride to nitric acid, a strong solvent capable of dissolving gold (i.e., "aqua regia") could be produced. Although "aqua regia" is an unstable mixture that continually gives off fumes containing free chlorine gas, this chlorine gas appears to have been ignored until c. 1630, when its nature as a separate gaseous substance was recognised by the Brabantian chemist and physician Jan Baptist van Helmont.


title: Chlorine

text: The element was first studied in detail in 1774 by Swedish chemist Carl Wilhelm Scheele, and he is credited with the discovery. Scheele produced chlorine by reacting MnO (as the mineral pyrolusite) with HCl:


title: Chlorine

text: Scheele observed several of the properties of chlorine: the bleaching effect on litmus, the deadly effect on insects, the yellow-green color, and the smell similar to aqua regia. He called it ""dephlogisticated muriatic acid air"" since it is a gas (then called "airs") and it came from hydrochloric acid (then known as "muriatic acid"). He failed to establish chlorine as an element.


title: Chlorine

text: Common chemical theory at that time held that an acid is a compound that contains oxygen (remnants of this survive in the German and Dutch names of oxygen: "sauerstoff" or "zuurstof", both translating into English as "acid substance"), so a number of chemists, including Claude Berthollet, suggested that Scheele's "dephlogisticated muriatic acid air" must be a combination of oxygen and the yet undiscovered element, "muriaticum".


title: Chlorine

text: In 1809, Joseph Louis Gay-Lussac and Louis-Jacques Thénard tried to decompose "dephlogisticated muriatic acid air" by reacting it with charcoal to release the free element "muriaticum" (and carbon dioxide). They did not succeed and published a report in which they considered the possibility that "dephlogisticated muriatic acid air" is an element, but were not convinced.


title: Chlorine

text: In 1810, Sir Humphry Davy tried the same experiment again, and concluded that the substance was an element, and not a compound. He announced his results to the Royal Society on 15 November that year. At that time, he named this new element "chlorine", from the Greek word χλωρος ("chlōros", "green-yellow"), in reference to its color. The name "halogen", meaning "salt producer", was originally used for chlorine in 1811 by Johann Salomo Christoph Schweigger. This term was later used as a generic term to describe all the elements in the chlorine family (fluorine, bromine, iodine), after a suggestion by Jöns Jakob Berzelius in 1826. In 1823, Michael Faraday liquefied chlorine for the first time, and demonstrated that what was then known as "solid chlorine" had a structure of chlorine hydrate (Cl·HO).


title: Chlorine

text: Chlorine gas was first used by French chemist Claude Berthollet to bleach textiles in 1785. Modern bleaches resulted from further work by Berthollet, who first produced sodium hypochlorite in 1789 in his laboratory in the town of Javel (now part of Paris, France), by passing chlorine gas through a solution of sodium carbonate. The resulting liquid, known as ""Eau de Javel"" ("Javel water"), was a weak solution of sodium hypochlorite. This process was not very efficient, and alternative production methods were sought. Scottish chemist and industrialist Charles Tennant first produced a solution of calcium hypochlorite ("chlorinated lime"), then solid calcium hypochlorite (bleaching powder). These compounds produced low levels of elemental chlorine and could be more efficiently transported than sodium hypochlorite, which remained as dilute solutions because when purified to eliminate water, it became a dangerously powerful and unstable oxidizer. Near the end of the nineteenth century, E. S. Smith patented a method of sodium hypochlorite production involving electrolysis of brine to produce sodium hydroxide and chlorine gas, which then mixed to form sodium hypochlorite. This is known as the chloralkali process, first introduced on an industrial scale in 1892, and now the source of most elemental chlorine and sodium hydroxide. In 1884 Chemischen Fabrik Griesheim of Germany developed another chloralkali process which entered commercial production in 1888.


title: Chlorine

text: Elemental chlorine solutions dissolved in chemically basic water (sodium and calcium hypochlorite) were first used as anti-putrefaction agents and disinfectants in the 1820s, in France, long before the establishment of the germ theory of disease. This practice was pioneered by Antoine-Germain Labarraque, who adapted Berthollet's "Javel water" bleach and other chlorine preparations (for a more complete history, see below). Elemental chlorine has since served a continuous function in topical antisepsis (wound irrigation solutions and the like) and public sanitation, particularly in swimming and drinking water.


title: Chlorine

text: Chlorine gas was first used as a weapon on April 22, 1915, at Ypres by the German Army. The effect on the allies was devastating because the existing gas masks were difficult to deploy and had not been broadly distributed.


title: Chlorine

text: Chlorine is the second halogen, being a nonmetal in group 17 of the periodic table. Its properties are thus similar to fluorine, bromine, and iodine, and are largely intermediate between those of the first two. Chlorine has the electron configuration [Ne]3s3p, with the seven electrons in the third and outermost shell acting as its valence electrons. Like all halogens, it is thus one electron short of a full octet, and is hence a strong oxidising agent, reacting with many elements in order to complete its outer shell. Corresponding to periodic trends, it is intermediate in electronegativity between fluorine and bromine (F: 3.98, Cl: 3.16, Br: 2.96, I: 2.66), and is less reactive than fluorine and more reactive than bromine. It is also a weaker oxidising agent than fluorine, but a stronger one than bromine. Conversely, the chloride ion is a weaker reducing agent than bromide, but a stronger one than fluoride. It is intermediate in atomic radius between fluorine and bromine, and this leads to many of its atomic properties similarly continuing the trend from iodine to bromine upward, such as first ionisation energy, electron affinity, enthalpy of dissociation of the X molecule (X = Cl, Br, I), ionic radius, and X–X bond length. (Fluorine is anomalous due to its small size.)


title: Chlorine

text: All four stable halogens experience intermolecular van der Waals forces of attraction, and their strength increases together with the number of electrons among all homonuclear diatomic halogen molecules. Thus, the melting and boiling points of chlorine are intermediate between those of fluorine and bromine: chlorine melts at −101.0 °C and boils at −34.0 °C. As a result of the increasing molecular weight of the halogens down the group, the density and heats of fusion and vaporisation of chlorine are again intermediate between those of bromine and fluorine, although all their heats of vaporisation are fairly low (leading to high volatility) thanks to their diatomic molecular structure. The halogens darken in colour as the group is descended: thus, while fluorine is a pale yellow gas, chlorine is distinctly yellow-green. This trend occurs because the wavelengths of visible light absorbed by the halogens increase down the group. Specifically, the colour of a halogen, such as chlorine, results from the electron transition between the highest occupied antibonding "π" molecular orbital and the lowest vacant antibonding "σ" molecular orbital. The colour fades at low temperatures, so that solid chlorine at −195 °C is almost colourless.


title: Chlorine

text: Like solid bromine and iodine, solid chlorine crystallises in the orthorhombic crystal system, in a layered lattice of Cl molecules. The Cl–Cl distance is 198 pm (close to the gaseous Cl–Cl distance of 199 pm) and the Cl···Cl distance between molecules is 332 pm within a layer and 382 pm between layers (compare the van der Waals radius of chlorine, 180 pm). This structure means that chlorine is a very poor conductor of electricity, and indeed its conductivity is so low as to be practically unmeasurable.


title: Chlorine

text: Chlorine has two stable isotopes, Cl and Cl. These are its only two natural isotopes occurring in quantity, with Cl making up 76% of natural chlorine and Cl making up the remaining 24%. Both are synthesised in stars in the oxygen-burning and silicon-burning processes. Both have nuclear spin 3/2+ and thus may be used for nuclear magnetic resonance, although the spin magnitude being greater than 1/2 results in non-spherical nuclear charge distribution and thus resonance broadening as a result of a nonzero nuclear quadrupole moment and resultant quadrupolar relaxation. The other chlorine isotopes are all radioactive, with half-lives too short to occur in nature primordially. Of these, the most commonly used in the laboratory are Cl ("t" = 3.0×10 y) and Cl ("t" = 37.2 min), which may be produced from the neutron activation of natural chlorine.


title: Chlorine

text: The most stable chlorine radioisotope is Cl. The primary decay mode of isotopes lighter than Cl is electron capture to isotopes of sulfur; that of isotopes heavier than Cl is beta decay to isotopes of argon; and Cl may decay by either mode to stable S or Ar. Cl occurs in trace quantities in nature as a cosmogenic nuclide in a ratio of about (7–10) × 10 to 1 with stable chlorine isotopes: it is produced in the atmosphere by spallation of Ar by interactions with cosmic ray protons. In the top meter of the lithosphere, Cl is generated primarily by thermal neutron activation of Cl and spallation of K and Ca. In the subsurface environment, muon capture by Ca becomes more important as a way to generate Cl.


title: Chlorine

text: Chlorine is intermediate in reactivity between fluorine and bromine, and is one of the most reactive elements. Chlorine is a weaker oxidising agent than fluorine but a stronger one than bromine or iodine. This can be seen from the standard electrode potentials of the X/X couples (F, +2.866 V; Cl, +1.395 V; Br, +1.087 V; I, +0.615 V; At, approximately +0.3 V). However, this trend is not shown in the bond energies because fluorine is singular due to its small size, low polarisability, and inability to show hypervalence. As another difference, chlorine has a significant chemistry in positive oxidation states while fluorine does not. Chlorination often leads to higher oxidation states than bromination or iodination but lower oxidation states than fluorination. Chlorine tends to react with compounds including M–M, M–H, or M–C bonds to form M–Cl bonds.


title: Chlorine

text: Given that E°(O/HO) = +1.229 V, which is less than +1.395 V, it would be expected that chlorine should be able to oxidise water to oxygen and hydrochloric acid. However, the kinetics of this reaction are unfavorable, and there is also a bubble overpotential effect to consider, so that electrolysis of aqueous chloride solutions evolves chlorine gas and not oxygen gas, a fact that is very useful for the industrial production of chlorine.


title: Chlorine

text: The simplest chlorine compound is hydrogen chloride, HCl, a major chemical in industry as well as in the laboratory, both as a gas and dissolved in water as hydrochloric acid. It is often produced by burning hydrogen gas in chlorine gas, or as a byproduct of chlorinating hydrocarbons. Another approach is to treat sodium chloride with concentrated sulfuric acid to produce hydrochloric acid, also known as the "salt-cake" process:


title: Chlorine

text: In the laboratory, hydrogen chloride gas may be made by drying the acid with concentrated sulfuric acid. Deuterium chloride, DCl, may be produced by reacting benzoyl chloride with heavy water (DO).


title: Chlorine

text: At room temperature, hydrogen chloride is a colourless gas, like all the hydrogen halides apart from hydrogen fluoride, since hydrogen cannot form strong hydrogen bonds to the larger electronegative chlorine atom; however, weak hydrogen bonding is present in solid crystalline hydrogen chloride at low temperatures, similar to the hydrogen fluoride structure, before disorder begins to prevail as the temperature is raised. Hydrochloric acid is a strong acid (p"K" = −7) because the hydrogen bonds to chlorine are too weak to inhibit dissociation. The HCl/HO system has many hydrates HCl·"n"HO for "n" = 1, 2, 3, 4, and 6. Beyond a 1:1 mixture of HCl and HO, the system separates completely into two separate liquid phases. Hydrochloric acid forms an azeotrope with boiling point 108.58 °C at 20.22 g HCl per 100 g solution; thus hydrochloric acid cannot be concentrated beyond this point by distillation.


title: Chlorine

text: Unlike hydrogen fluoride, anhydrous liquid hydrogen chloride is difficult to work with as a solvent, because its boiling point is low, it has a small liquid range, its dielectric constant is low and it does not dissociate appreciably into HCl and ions – the latter, in any case, are much less stable than the bifluoride ions () due to the very weak hydrogen bonding between hydrogen and chlorine, though its salts with very large and weakly polarising cations such as Cs and (R = Me, Et, Bu) may still be isolated. Anhydrous hydrogen chloride is a poor solvent, only able to dissolve small molecular compounds such as nitrosyl chloride and phenol, or salts with very low lattice energies such as tetraalkylammonium halides. It readily protonates electrophiles containing lone-pairs or π bonds. Solvolysis, ligand replacement reactions, and oxidations are well-characterised in hydrogen chloride solution:


title: Chlorine

text: Nearly all elements in the periodic table form binary chlorides. The exceptions are decidedly in the minority and stem in each case from one of three causes: extreme inertness and reluctance to participate in chemical reactions (the noble gases, with the exception of xenon in the highly unstable XeCl and XeCl); extreme nuclear instability hampering chemical investigation before decay and transmutation (many of the heaviest elements beyond bismuth); and having an electronegativity higher than chlorine's (oxygen and fluorine) so that the resultant binary compounds are formally not chlorides but rather oxides or fluorides of chlorine. Even though nitrogen in NCl is bearing a negative charge, the compound is usually called nitrogen trichloride.


title: Chlorine

text: Chlorination of metals with Cl usually leads to a higher oxidation state than bromination with Br when multiple oxidation states are available, such as in MoCl and MoBr. Chlorides can be made by reaction of an element or its oxide, hydroxide, or carbonate with hydrochloric acid, and then dehydrated by mildly high temperatures combined with either low pressure or anhydrous hydrogen chloride gas. These methods work best when the chloride product is stable to hydrolysis; otherwise, the possibilities include high-temperature oxidative chlorination of the element with chlorine or hydrogen chloride, high-temperature chlorination of a metal oxide or other halide by chlorine, a volatile metal chloride, carbon tetrachloride, or an organic chloride. For instance, zirconium dioxide reacts with chlorine at standard conditions to produce zirconium tetrachloride, and uranium trioxide reacts with hexachloropropene when heated under reflux to give uranium tetrachloride. The second example also involves a reduction in oxidation state, which can also be achieved by reducing a higher chloride using hydrogen or a metal as a reducing agent. This may also be achieved by thermal decomposition or disproportionation as follows:


title: Chlorine

text: Most metal chlorides with the metal in low oxidation states (+1 to +3) are ionic. Nonmetals tend to form covalent molecular chlorides, as do metals in high oxidation states from +3 and above. Both ionic and covalent chlorides are known for metals in oxidation state +3 (e.g. scandium chloride is mostly ionic, but aluminium chloride is not). Silver chloride is very insoluble in water and is thus often used as a qualitative test for chlorine.


title: Chlorine

text: Although dichlorine is a strong oxidising agent with a high first ionisation energy, it may be oxidised under extreme conditions to form the cation. This is very unstable and has only been characterised by its electronic band spectrum when produced in a low-pressure discharge tube. The yellow cation is more stable and may be produced as follows:


title: Chlorine

text: This reaction is conducted in the oxidising solvent arsenic pentafluoride. The trichloride anion, , has also been characterised; it is analogous to triiodide.


title: Chlorine

text: The three fluorides of chlorine form a subset of the interhalogen compounds, all of which are diamagnetic. Some cationic and anionic derivatives are known, such as , , , and ClF. Some pseudohalides of chlorine are also known, such as cyanogen chloride (ClCN, linear), chlorine cyanate (ClNCO), chlorine thiocyanate (ClSCN, unlike its oxygen counterpart), and chlorine azide (ClN).


title: Chlorine

text: Chlorine monofluoride (ClF) is extremely thermally stable, and is sold commercially in 500-gram steel lecture bottles. It is a colourless gas that melts at −155.6 °C and boils at −100.1 °C. It may be produced by the direction of its elements at 225 °C, though it must then be separated and purified from chlorine trifluoride and its reactants. Its properties are mostly intermediate between those of chlorine and fluorine. It will react with many metals and nonmetals from room temperature and above, fluorinating them and liberating chlorine. It will also act as a chlorofluorinating agent, adding chlorine and fluorine across a multiple bond or by oxidation: for example, it will attack carbon monoxide to form carbonyl chlorofluoride, COFCl. It will react analogously with hexafluoroacetone, (CF)CO, with a potassium fluoride catalyst to produce heptafluoroisopropyl hypochlorite, (CF)CFOCl; with nitriles RCN to produce RCFNCl; and with the sulfur oxides SO and SO to produce ClSOF and ClOSOF respectively. It will also react exothermically with compounds containing –OH and –NH groups, such as water:


title: Chlorine

text: Chlorine trifluoride (ClF) is a volatile colourless molecular liquid which melts at −76.3 °C and boils at 11.8 °C. It may be formed by directly fluorinating gaseous chlorine or chlorine monofluoride at 200–300 °C. One of the most reactive chemical compounds known, the list of elements it sets on fire is diverse, containing hydrogen, potassium, phosphorus, arsenic, antimony, sulfur, selenium, tellurium, bromine, iodine, and powdered molybdenum, tungsten, rhodium, iridium, and iron. It will also ignite water, along with many substances which in ordinary circumstances would be considered chemically inert such as asbestos, concrete, glass, and sand. When heated, it will even corrode noble metals as palladium, platinum, and gold, and even the noble gases xenon and radon do not escape fluorination. An impermeable fluoride layer is formed by sodium, magnesium, aluminium, zinc, tin, and silver, which may be removed by heating. Nickel, copper, and steel containers are usually used due to their great resistance to attack by chlorine trifluoride, stemming from the formation of an unreactive layer of metal fluoride. Its reaction with hydrazine to form hydrogen fluoride, nitrogen, and chlorine gases was used in experimental rocket engine, but has problems largely stemming from its extreme hypergolicity resulting in ignition without any measurable delay. Today, it is mostly used in nuclear fuel processing, to oxidise uranium to uranium hexafluoride for its enriching and to separate it from plutonium, as well as in the semiconductor industry, where it is used to clean chemical vapor deposition chambers. It can act as a fluoride ion donor or acceptor (Lewis base or acid), although it does not dissociate appreciably into and ions.


title: Chlorine

text: Chlorine pentafluoride (ClF) is made on a large scale by direct fluorination of chlorine with excess fluorine gas at 350 °C and 250 atm, and on a small scale by reacting metal chlorides with fluorine gas at 100–300 °C. It melts at −103 °C and boils at −13.1 °C. It is a very strong fluorinating agent, although it is still not as effective as chlorine trifluoride. Only a few specific stoichiometric reactions have been characterised. Arsenic pentafluoride and antimony pentafluoride form ionic adducts of the form [ClF][MF] (M = As, Sb) and water reacts vigorously as follows:


title: Chlorine

text: The product, chloryl fluoride, is one of the five known chlorine oxide fluorides. These range from the thermally unstable FClO to the chemically unreactive perchloryl fluoride (FClO), the other three being FClO, FClO, and FClO. All five behave similarly to the chlorine fluorides, both structurally and chemically, and may act as Lewis acids or bases by gaining or losing fluoride ions respectively or as very strong oxidising and fluorinating agents.


title: Chlorine

text: The chlorine oxides are well-studied in spite of their instability (all of them are endothermic compounds). They are important because they are produced when chlorofluorocarbons undergo photolysis in the upper atmosphere and cause the destruction of the ozone layer. None of them can be made from directly reacting the elements.


title: Chlorine

text: Dichlorine monoxide (ClO) is a brownish-yellow gas (red-brown when solid or liquid) which may be obtained by reacting chlorine gas with yellow mercury(II) oxide. It is very soluble in water, in which it is in equilibrium with hypochlorous acid (HOCl), of which it is the anhydride. It is thus an effective bleach and is mostly used to make hypochlorites. It explodes on heating or sparking or in the presence of ammonia gas.


title: Chlorine

text: Chlorine dioxide (ClO) was the first chlorine oxide to be discovered in 1811 by Humphry Davy. It is a yellow paramagnetic gas (deep-red as a solid or liquid), as expected from its having an odd number of electrons: it is stable towards dimerisation due to the delocalisation of the unpaired electron. It explodes above −40 °C as a liquid and under pressure as a gas and therefore must be made at low concentrations for wood-pulp bleaching and water treatment. It is usually prepared by reducing a chlorate as follows:


title: Chlorine

text: Its production is thus intimately linked to the redox reactions of the chlorine oxoacids. It is a strong oxidising agent, reacting with sulfur, phosphorus, phosphorus halides, and potassium borohydride. It dissolves exothermically in water to form dark-green solutions that very slowly decompose in the dark. Crystalline clathrate hydrates ClO·"n"HO ("n" ≈ 6–10) separate out at low temperatures. However, in the presence of light, these solutions rapidly photodecompose to form a mixture of chloric and hydrochloric acids. Photolysis of individual ClO molecules result in the radicals ClO and ClOO, while at room temperature mostly chlorine, oxygen, and some ClO and ClO are produced. ClO is also produced when photolysing the solid at −78 °C: it is a dark brown solid that explodes below 0 °C. The ClO radical leads to the depletion of atmospheric ozone and is thus environmentally important as follows:


title: Chlorine

text: Chlorine perchlorate (ClOClO) is a pale yellow liquid that is less stable than ClO and decomposes at room temperature to form chlorine, oxygen, and dichlorine hexoxide (ClO). Chlorine perchlorate may also be considered a chlorine derivative of perchloric acid (HOClO), similar to the thermally unstable chlorine derivatives of other oxoacids: examples include chlorine nitrate (ClONO, vigorously reactive and explosive), and chlorine fluorosulfate (ClOSOF, more stable but still moisture-sensitive and highly reactive). Dichlorine hexoxide is a dark-red liquid that freezes to form a solid which turns yellow at −180 °C: it is usually made by reaction of chlorine dioxide with oxygen. Despite attempts to rationalise it as the dimer of ClO, it reacts more as though it were chloryl perchlorate, [ClO][ClO], which has been confirmed to be the correct structure of the solid. It hydrolyses in water to give a mixture of chloric and perchloric acids: the analogous reaction with anhydrous hydrogen fluoride does not proceed to completion.


title: Chlorine

text: Dichlorine heptoxide (ClO) is the anhydride of perchloric acid (HClO) and can readily be obtained from it by dehydrating it with phosphoric acid at −10 °C and then distilling the product at −35 °C and 1 mmHg. It is a shock-sensitive, colourless oily liquid. It is the least reactive of the chlorine oxides, being the only one to not set organic materials on fire at room temperature. It may be dissolved in water to regenerate perchloric acid or in aqueous alkalis to regenerate perchlorates. However, it thermally decomposes explosively by breaking one of the central Cl–O bonds, producing the radicals ClO and ClO which immediately decompose to the elements through intermediate oxides.


title: Chlorine

text: Chlorine forms four oxoacids: hypochlorous acid (HOCl), chlorous acid (HOClO), chloric acid (HOClO), and perchloric acid (HOClO). As can be seen from the redox potentials given in the adjacent table, chlorine is much more stable towards disproportionation in acidic solutions than in alkaline solutions:


title: Chlorine

text: The hypochlorite ions also disproportionate further to produce chloride and chlorate (3 ClO 2 Cl + ) but this reaction is quite slow at temperatures below 70 °C in spite of the very favourable equilibrium constant of 10. The chlorate ions may themselves disproportionate to form chloride and perchlorate (4 Cl + 3 ) but this is still very slow even at 100 °C despite the very favourable equilibrium constant of 10. The rates of reaction for the chlorine oxyanions increases as the oxidation state of chlorine decreases. The strengths of the chlorine oxyacids increase very quickly as the oxidation state of chlorine increases due to the increasing delocalisation of charge over more and more oxygen atoms in their conjugate bases.


title: Chlorine

text: Most of the chlorine oxoacids may be produced by exploiting these disproportionation reactions. Hypochlorous acid (HOCl) is highly reactive and quite unstable; its salts are mostly used for their bleaching and sterilising abilities. They are very strong oxidising agents, transferring an oxygen atom to most inorganic species. Chlorous acid (HOClO) is even more unstable and cannot be isolated or concentrated without decomposition: it is known from the decomposition of aqueous chlorine dioxide. However, sodium chlorite is a stable salt and is useful for bleaching and stripping textiles, as an oxidising agent, and as a source of chlorine dioxide. Chloric acid (HOClO) is a strong acid that is quite stable in cold water up to 30% concentration, but on warming gives chlorine and chlorine dioxide. Evaporation under reduced pressure allows it to be concentrated further to about 40%, but then it decomposes to perchloric acid, chlorine, oxygen, water, and chlorine dioxide. Its most important salt is sodium chlorate, mostly used to make chlorine dioxide to bleach paper pulp. The decomposition of chlorate to chloride and oxygen is a common way to produce oxygen in the laboratory on a small scale. Chloride and chlorate may comproportionate to form chlorine as follows:


title: Chlorine

text: Perchlorates and perchloric acid (HOClO) are the most stable oxo-compounds of chlorine, in keeping with the fact that chlorine compounds are most stable when the chlorine atom is in its lowest (−1) or highest (+7) possible oxidation states. Perchloric acid and aqueous perchlorates are vigorous and sometimes violent oxidising agents when heated, in stark contrast to their mostly inactive nature at room temperature due to the high activation energies for these reactions for kinetic reasons. Perchlorates are made by electrolytically oxidising sodium chlorate, and perchloric acid is made by reacting anhydrous sodium perchlorate or barium perchlorate with concentrated hydrochloric acid, filtering away the chloride precipitated and distilling the filtrate to concentrate it. Anhydrous perchloric acid is a colourless mobile liquid that is sensitive to shock that explodes on contact with most organic compounds, sets hydrogen iodide and thionyl chloride on fire and even oxidises silver and gold. Although it is a weak ligand, weaker than water, a few compounds involving coordinated are known.


title: Chlorine

text: Like the other carbon–halogen bonds, the C–Cl bond is a common functional group that forms part of core organic chemistry. Formally, compounds with this functional group may be considered organic derivatives of the chloride anion. Due to the difference of electronegativity between chlorine (3.16) and carbon (2.55), the carbon in a C–Cl bond is electron-deficient and thus electrophilic. Chlorination modifies the physical properties of hydrocarbons in several ways: chlorocarbons are typically denser than water due to the higher atomic weight of chlorine versus hydrogen, and aliphatic organochlorides are alkylating agents because chloride is a leaving group.


title: Chlorine

text: Alkanes and aryl alkanes may be chlorinated under free-radical conditions, with UV light. However, the extent of chlorination is difficult to control: the reaction is not regioselective and often results in a mixture of various isomers with different degrees of chlorination, though this may be permissible if the products are easily separated. Aryl chlorides may be prepared by the Friedel-Crafts halogenation, using chlorine and a Lewis acid catalyst. The haloform reaction, using chlorine and sodium hydroxide, is also able to generate alkyl halides from methyl ketones, and related compounds. Chlorine adds to the multiple bonds on alkenes and alkynes as well, giving di- or tetra-chloro compounds. However, due to the expense and reactivity of chlorine, organochlorine compounds are more commonly produced by using hydrogen chloride, or with chlorinating agents such as phosphorus pentachloride (PCl) or thionyl chloride (SOCl). The last is very convenient in the laboratory because all side products are gaseous and do not have to be distilled out.


title: Chlorine

text: Many organochlorine compounds have been isolated from natural sources ranging from bacteria to humans. Chlorinated organic compounds are found in nearly every class of biomolecules including alkaloids, terpenes, amino acids, flavonoids, steroids, and fatty acids. Organochlorides, including dioxins, are produced in the high temperature environment of forest fires, and dioxins have been found in the preserved ashes of lightning-ignited fires that predate synthetic dioxins. In addition, a variety of simple chlorinated hydrocarbons including dichloromethane, chloroform, and carbon tetrachloride have been isolated from marine algae. A majority of the chloromethane in the environment is produced naturally by biological decomposition, forest fires, and volcanoes.


title: Chlorine

text: Some types of organochlorides, though not all, have significant toxicity to plants or animals, including humans. Dioxins, produced when organic matter is burned in the presence of chlorine, and some insecticides, such as DDT, are persistent organic pollutants which pose dangers when they are released into the environment. For example, DDT, which was widely used to control insects in the mid 20th century, also accumulates in food chains, and causes reproductive problems (e.g., eggshell thinning) in certain bird species. Due to the ready homolytic fission of the C–Cl bond to create chlorine radicals in the upper atmosphere, chlorofluorocarbons have been phased out due to the harm they do to the ozone layer.


title: Chlorine

text: Chlorine is too reactive to occur as the free element in nature but is very abundant in the form of its chloride salts. It is the twenty-first most abundant element in Earth's crust and makes up 126 parts per million of it, through the large deposits of chloride minerals, especially sodium chloride, that have been evaporated from water bodies. All of these pale in comparison to the reserves of chloride ions in seawater: smaller amounts at higher concentrations occur in some inland seas and underground brine wells, such as the Great Salt Lake in Utah and the Dead Sea in Israel.


title: Chlorine

text: Small batches of chlorine gas are prepared in the laboratory by combining hydrochloric acid and manganese dioxide, but the need rarely arises due to its ready availability. In industry, elemental chlorine is usually produced by the electrolysis of sodium chloride dissolved in water. This method, the chloralkali process industrialized in 1892, now provides most industrial chlorine gas. Along with chlorine, the method yields hydrogen gas and sodium hydroxide, which is the most valuable product. The process proceeds according to the following chemical equation:


title: Chlorine

text: In diaphragm cell electrolysis, an asbestos (or polymer-fiber) diaphragm separates a cathode and an anode, preventing the chlorine forming at the anode from re-mixing with the sodium hydroxide and the hydrogen formed at the cathode. The salt solution (brine) is continuously fed to the anode compartment and flows through the diaphragm to the cathode compartment, where the caustic alkali is produced and the brine is partially depleted. Diaphragm methods produce dilute and slightly impure alkali, but they are not burdened with the problem of mercury disposal and they are more energy efficient.


title: Chlorine

text: Membrane cell electrolysis employs permeable membrane as an ion exchanger. Saturated sodium (or potassium) chloride solution is passed through the anode compartment, leaving at a lower concentration. This method also produces very pure sodium (or potassium) hydroxide but has the disadvantage of requiring very pure brine at high concentrations.


title: Chlorine

text: In the Deacon process, hydrogen chloride recovered from the production of organochlorine compounds is recovered as chlorine. The process relies on oxidation using oxygen:


title: Chlorine

text: The reaction requires a catalyst. As introduced by Deacon, early catalysts were based on copper. Commercial processes, such as the Mitsui MT-Chlorine Process, have switched to chromium and ruthenium-based catalysts. The chlorine produced is available in cylinders from sizes ranging from 450 g to 70 kg, as well as drums (865 kg), tank wagons (15 tonnes on roads; 27–90 tonnes by rail), and barges (600–1200 tonnes).


title: Chlorine

text: Sodium chloride is the most common chlorine compound, and is the main source of chlorine for the demand by the chemical industry. About 15000 chlorine-containing compounds are commercially traded, including such diverse compounds as chlorinated methane, ethanes, vinyl chloride, polyvinyl chloride (PVC), aluminium trichloride for catalysis, the chlorides of magnesium, titanium, zirconium, and hafnium which are the precursors for producing the pure form of those elements.


title: Chlorine

text: Quantitatively, of all elemental chlorine produced, about 63% is used in the manufacture of organic compounds, and 18% in the manufacture of inorganic chlorine compounds. About 15,000 chlorine compounds are used commercially. The remaining 19% of chlorine produced is used for bleaches and disinfection products. The most significant of organic compounds in terms of production volume are 1,2-dichloroethane and vinyl chloride, intermediates in the production of PVC. Other particularly important organochlorines are methyl chloride, methylene chloride, chloroform, vinylidene chloride, trichloroethylene, perchloroethylene, allyl chloride, epichlorohydrin, chlorobenzene, dichlorobenzenes, and trichlorobenzenes. The major inorganic compounds include HCl, ClO, HOCl, NaClO, chlorinated isocyanurates, AlCl, SiCl, SnCl, PCl, PCl, POCl, AsCl, SbCl, SbCl, BiCl, and ZnCl.


title: Chlorine

text: In France (as elsewhere), animal intestines were processed to make musical instrument strings, Goldbeater's skin and other products. This was done in "gut factories" ("boyauderies"), and it was an odiferous and unhealthy process. In or about 1820, the Société d'encouragement pour l'industrie nationale offered a prize for the discovery of a method, chemical or mechanical, for separating the peritoneal membrane of animal intestines without putrefaction. The prize was won by Antoine-Germain Labarraque, a 44-year-old French chemist and pharmacist who had discovered that Berthollet's chlorinated bleaching solutions (""Eau de Javel"") not only destroyed the smell of putrefaction of animal tissue decomposition, but also actually retarded the decomposition.


title: Chlorine

text: Labarraque's research resulted in the use of chlorides and hypochlorites of lime (calcium hypochlorite) and of sodium (sodium hypochlorite) in the "boyauderies." The same chemicals were found to be useful in the routine disinfection and deodorization of latrines, sewers, markets, abattoirs, anatomical theatres, and morgues. They were successful in hospitals, lazarets, prisons, infirmaries (both on land and at sea), magnaneries, stables, cattle-sheds, etc.; and they were beneficial during exhumations, embalming, outbreaks of epidemic disease, fever, and blackleg in cattle.


title: Chlorine

text: Labarraque's chlorinated lime and soda solutions have been advocated since 1828 to prevent infection (called "contagious infection", presumed to be transmitted by "miasmas"), and to treat putrefaction of existing wounds, including septic wounds. In his 1828 work, Labarraque recommended that doctors breathe chlorine, wash their hands in chlorinated lime, and even sprinkle chlorinated lime about the patients' beds in cases of "contagious infection". In 1828, the contagion of infections was well known, even though the agency of the microbe was not discovered until more than half a century later.


title: Chlorine

text: During the Paris cholera outbreak of 1832, large quantities of so-called "chloride of lime" were used to disinfect the capital. This was not simply modern calcium chloride, but chlorine gas dissolved in lime-water (dilute calcium hydroxide) to form calcium hypochlorite (chlorinated lime). Labarraque's discovery helped to remove the terrible stench of decay from hospitals and dissecting rooms, and by doing so, effectively deodorised the Latin Quarter of Paris. These "putrid miasmas" were thought by many to cause the spread of "contagion" and "infection" – both words used before the germ theory of infection. Chloride of lime was used for destroying odors and "putrid matter". One source claims chloride of lime was used by Dr. John Snow to disinfect water from the cholera-contaminated well that was feeding the Broad Street pump in 1854 London, though three other reputable sources that describe that famous cholera epidemic do not mention the incident. One reference makes it clear that chloride of lime was used to disinfect the offal and filth in the streets surrounding the Broad Street pump – a common practice in mid-nineteenth century England.


title: Chlorine

text: Perhaps the most famous application of Labarraque's chlorine and chemical base solutions was in 1847, when Ignaz Semmelweis used chlorine-water (chlorine dissolved in pure water, which was cheaper than chlorinated lime solutions) to disinfect the hands of Austrian doctors, which Semmelweis noticed still carried the stench of decomposition from the dissection rooms to the patient examination rooms. Long before the germ theory of disease, Semmelweis theorized that "cadaveric particles" were transmitting decay from fresh medical cadavers to living patients, and he used the well-known "Labarraque's solutions" as the only known method to remove the smell of decay and tissue decomposition (which he found that soap did not). The solutions proved to be far more effective antiseptics than soap (Semmelweis was also aware of their greater efficacy, but not the reason), and this resulted in Semmelweis's celebrated success in stopping the transmission of childbed fever ("puerperal fever") in the maternity wards of Vienna General Hospital in Austria in 1847.


title: Chlorine

text: Much later, during World War I in 1916, a standardized and diluted modification of Labarraque's solution containing hypochlorite (0.5%) and boric acid as an acidic stabilizer was developed by Henry Drysdale Dakin (who gave full credit to Labarraque's prior work in this area). Called Dakin's solution, the method of wound irrigation with chlorinated solutions allowed antiseptic treatment of a wide variety of open wounds, long before the modern antibiotic era. A modified version of this solution continues to be employed in wound irrigation in modern times, where it remains effective against bacteria that are resistant to multiple antibiotics (see Century Pharmaceuticals).


title: Chlorine

text: The first continuous application of chlorination to drinking U.S. water was installed in Jersey City, New Jersey, in 1908. By 1918, the US Department of Treasury called for all drinking water to be disinfected with chlorine. Chlorine is presently an important chemical for water purification (such as in water treatment plants), in disinfectants, and in bleach. Even small water supplies are now routinely chlorinated.


title: Chlorine

text: Chlorine is usually used (in the form of hypochlorous acid) to kill bacteria and other microbes in drinking water supplies and public swimming pools. In most private swimming pools, chlorine itself is not used, but rather sodium hypochlorite, formed from chlorine and sodium hydroxide, or solid tablets of chlorinated isocyanurates. The drawback of using chlorine in swimming pools is that the chlorine reacts with the amino acids in proteins in human hair and skin. Contrary to popular belief, the distinctive "chlorine aroma" associated with swimming pools is not the result of elemental chlorine itself, but of chloramine, a chemical compound produced by the reaction of free dissolved chlorine with amines in organic substances including those in urine and sweat. As a disinfectant in water, chlorine is more than three times as effective against "Escherichia coli" as bromine, and more than six times as effective as iodine. Increasingly, monochloramine itself is being directly added to drinking water for purposes of disinfection, a process known as chloramination.


title: Chlorine

text: It is often impractical to store and use poisonous chlorine gas for water treatment, so alternative methods of adding chlorine are used. These include hypochlorite solutions, which gradually release chlorine into the water, and compounds like sodium dichloro-s-triazinetrione (dihydrate or anhydrous), sometimes referred to as "dichlor", and trichloro-s-triazinetrione, sometimes referred to as "trichlor". These compounds are stable while solid and may be used in powdered, granular, or tablet form. When added in small amounts to pool water or industrial water systems, the chlorine atoms hydrolyze from the rest of the molecule, forming hypochlorous acid (HOCl), which acts as a general biocide, killing germs, microorganisms, algae, and so on.


title: Chlorine

text: Chlorine gas, also known as bertholite, was first used as a weapon in World War I by Germany on April 22, 1915, in the Second Battle of Ypres. As described by the soldiers, it had the distinctive smell of a mixture of pepper and pineapple. It also tasted metallic and stung the back of the throat and chest. Chlorine reacts with water in the mucosa of the lungs to form hydrochloric acid, destructive to living tissue and potentially lethal. Human respiratory systems can be protected from chlorine gas by gas masks with activated charcoal or other filters, which makes chlorine gas much less lethal than other chemical weapons. It was pioneered by a German scientist later to be a Nobel laureate, Fritz Haber of the Kaiser Wilhelm Institute in Berlin, in collaboration with the German chemical conglomerate IG Farben, which developed methods for discharging chlorine gas against an entrenched enemy. After its first use, both sides in the conflict used chlorine as a chemical weapon, but it was soon replaced by the more deadly phosgene and mustard gas.


title: Chlorine

text: Chlorine gas was also used during the Iraq War in Anbar Province in 2007, with insurgents packing truck bombs with mortar shells and chlorine tanks. The attacks killed two people from the explosives and sickened more than 350. Most of the deaths were caused by the force of the explosions rather than the effects of chlorine since the toxic gas is readily dispersed and diluted in the atmosphere by the blast. In some bombings, over a hundred civilians were hospitalized due to breathing difficulties. The Iraqi authorities tightened security for elemental chlorine, which is essential for providing safe drinking water to the population.


title: Chlorine

text: On 23 October 2014, it was reported that the Islamic State of Iraq and the Levant had used chlorine gas in the town of Duluiyah, Iraq. Laboratory analysis of clothing and soil samples confirmed the use of chlorine gas against Kurdish Peshmerga Forces in a vehicle-borne improvised explosive device attack on 23 January 2015 at the Highway 47 Kiske Junction near Mosul.


title: Chlorine

text: Another country in the middle east, Syria, has used chlorine as a chemical weapon delivered from barrel bombs and rockets. In 2016, the OPCW-UN Joint Investigative Mechanism concluded that the Syrian government used chlorine as a chemical weapon in three separate attacks. Later investigations from the OPCW's Investigation and Identification Team concluded that the Syrian Air Force was responsible for chlorine attacks in 2017 and 2018.


title: Chlorine

text: The chloride anion is an essential nutrient for metabolism. Chlorine is needed for the production of hydrochloric acid in the stomach and in cellular pump functions. The main dietary source is table salt, or sodium chloride. Overly low or high concentrations of chloride in the blood are examples of electrolyte disturbances. Hypochloremia (having too little chloride) rarely occurs in the absence of other abnormalities. It is sometimes associated with hypoventilation. It can be associated with chronic respiratory acidosis. Hyperchloremia (having too much chloride) usually does not produce symptoms. When symptoms do occur, they tend to resemble those of hypernatremia (having too much sodium). Reduction in blood chloride leads to cerebral dehydration; symptoms are most often caused by rapid rehydration which results in cerebral edema. Hyperchloremia can affect oxygen transport.


title: Chlorine

text: Chlorine is a toxic gas that attacks the respiratory system, eyes, and skin. Because it is denser than air, it tends to accumulate at the bottom of poorly ventilated spaces. Chlorine gas is a strong oxidizer, which may react with flammable materials.


title: Chlorine

text: Chlorine is detectable with measuring devices in concentrations as low as 0.2 parts per million (ppm), and by smell at 3 ppm. Coughing and vomiting may occur at 30 ppm and lung damage at 60 ppm. About 1000 ppm can be fatal after a few deep breaths of the gas. The IDLH (immediately dangerous to life and health) concentration is 10 ppm. Breathing lower concentrations can aggravate the respiratory system and exposure to the gas can irritate the eyes. When chlorine is inhaled at concentrations greater than 30 ppm, it reacts with water within the lungs, producing hydrochloric acid (HCl) and hypochlorous acid (HClO).


title: Chlorine

text: When used at specified levels for water disinfection, the reaction of chlorine with water is not a major concern for human health. Other materials present in the water may generate disinfection by-products that are associated with negative effects on human health.


title: Chlorine

text: In the United States, the Occupational Safety and Health Administration (OSHA) has set the permissible exposure limit for elemental chlorine at 1 ppm, or 3 mg/m. The National Institute for Occupational Safety and Health has designated a recommended exposure limit of 0.5 ppm over 15 minutes.


title: Chlorine

text: In the home, accidents occur when hypochlorite bleach solutions come into contact with certain acidic drain-cleaners to produce chlorine gas. Hypochlorite bleach (a popular laundry additive) combined with ammonia (another popular laundry additive) produces chloramines, another toxic group of chemicals.


title: Chlorine

text: Chlorine is widely used for purifying water, especially potable water supplies and water used in swimming pools. Several catastrophic collapses of swimming pool ceilings have occurred from chlorine-induced stress corrosion cracking of stainless steel suspension rods. Some polymers are also sensitive to attack, including acetal resin and polybutene. Both materials were used in hot and cold water domestic plumbing, and stress corrosion cracking caused widespread failures in the US in the 1980s and 1990s.


title: Chlorine

text: The element iron can combine with chlorine at high temperatures in a strong exothermic reaction, creating a "chlorine-iron fire". Chlorine-iron fires are a risk in chemical process plants, where much of the pipework that carries chlorine gas is made of steel.


title: Ron Livingston

text: Ronald Joseph Livingston (born June 5, 1967) is an American actor. He is known for playing Peter Gibbons in the 1999 film "Office Space" and Captain Lewis Nixon III in the 2001 miniseries "Band of Brothers."


title: Ron Livingston

text: Livingston's other roles include the films "Swingers" (1996), "Adaptation" (2002), "The Conjuring" (2013); and the television series "Loudermilk", and "Boardwalk Empire", on which he appeared in the fourth season.


title: Ron Livingston

text: Livingston was born in Cedar Rapids, Iowa, to Kurt Livingston, an aerospace/electronics engineer, and Linda (née Rinas), a Lutheran pastor. His younger brother, John, is also an actor; while his sister, Jennifer Livingston, and brother-in-law, Mike Thompson, are TV news personalities at WKBT in La Crosse, Wisconsin.


title: Ron Livingston

text: Livingston attended Yale University, where he sang with The Whiffenpoofs and graduated in 1989, together with Anderson Cooper.


title: Ron Livingston

text: Livingston first acted at Theatre Cedar Rapids after being introduced to the group during a school job shadowing. Livingston moved to Chicago and became involved in the local theater scene.


title: Ron Livingston

text: Livingston's first film role was in 1992, in Dolly Parton's "Straight Talk". He moved to Los Angeles and was cast in supporting roles in "Some Folks Call it a Sling Blade" and "The Low Life". Livingston landed his first role in a major film in 1996's "Swingers". He starred as the male lead, Peter Gibbons, in the comedy cult classic "Office Space", which co-starred Jennifer Aniston and was written and directed by Mike Judge. He also appeared in HBO's miniseries "Band of Brothers" as Captain Lewis Nixon III opposite Donnie Wahlberg and Damian Lewis. Livingston widened his variety of roles when he played a Hollywood agent in "Adaptation" (2002), a weaselly Ivy League upstart opposite Alec Baldwin's casino boss in "The Cooler" (2003) and teachers in "Winter Solstice" and "Pretty Persuasion" (both 2005). He also appeared as sardonic writer Jack Berger, Carrie's short-term boyfriend in the fifth and sixth seasons of "Sex and the City". He guest-starred in the episode "TB or Not TB" of "House". In 2006, he starred as FBI negotiator Matt Flannery in the Fox series "Standoff", co-starring Rosemarie DeWitt, and he was an advertising spokesman for Sprint Nextel.


title: Ron Livingston

text: In summer 2007, Livingston appeared on the off-Broadway stage in the world premiere of Neil LaBute's "In a Dark Dark House", produced by "MCC Theater", with Frederick Weller and Louisa Krause. The show ran May–July at the Lucille Lortel Theatre in New York City. In November 2007, the indie film "Holly" told the story of a Vietnamese girl trafficked into the sex trade in Cambodia. Livingston starred as Patrick, a shady card shark who becomes determined to save Holly from her ill-destined fate.


title: Ron Livingston

text: In 2009, he portrayed flight engineer Maddux Donner in the series "Defying Gravity", which was cancelled after its first season.


title: Ron Livingston

text: In 2010, Livingston co-starred in the Jay Roach comedy "Dinner for Schmucks". On February 26, 2013, Entertainment Weekly confirmed that he would be joining the cast of HBO's "Boardwalk Empire" for the fourth season.


title: Ron Livingston

text: In 2013, Livingston co-starred in the indie comedy "Drinking Buddies" alongside Olivia Wilde, Jake Johnson and Anna Kendrick. "Drinking Buddies" received positive reviews from critics. "Rotten Tomatoes" gives the film a score of 82% based on 97 reviews.


title: Ron Livingston

text: Livingston starred in the Peter Farrelly–produced comedy television series "Loudermilk" on the Audience network. Livingston played the title role of Sam Loudermilk, a former music critic and recovering alcoholic who works as a substance abuse counselor and support group leader, and who regularly doles out clever but acid-tongued critiques to his clients, his friends, and random people he encounters. The show premiered in October 2017 and was renewed in April 2018 for a second season that premiered in October 2018. In December 2018, Audience renewed the series for a third season. After Audience ceased operations, the third season premiered on Amazon Prime Video in 2020–21.


title: Ron Livingston

text: Livingston also stars in the ABC drama "A Million Little Things" as Jon Dixon, whose suicide causes his group of friends to evaluate their own lives.


title: Ron Livingston

text: Livingston and his "Standoff" co-star Rosemarie DeWitt began a relationship after meeting on the show. After dating for three years, they were married on November 2, 2009, in San Francisco. He was previously engaged to actress Lisa Sheridan.


title: Ron Livingston

text: In May 2013, Livingston and his wife announced they had adopted an infant girl born the previous month. In December 2016, the couple announced they had adopted another child, a girl, who was born the previous year.


title: Michael Gandolfini

text: Michael Gandolfini (born May 10, 1999) is an American actor. Gandolfini made his film debut in "Ocean's 8" (2018) and appeared in "The Many Saints of Newark" (2021), in which he played the role of Tony Soprano, which was originally portrayed by his late father James Gandolfini in the television series "The Sopranos".


title: Michael Gandolfini

text: Gandolfini was born on May 10, 1999, in New York City to actor James Gandolfini and Marcy Wudarski. He is of Italian, Polish, and Slovak heritage, and has a younger half-sister from his father's second marriage. While he was a teenager Gandolfini enjoyed performing, but his father advised against an acting career instead wanting him to pursue sports or "be a director. They have the power," he said.


title: Michael Gandolfini

text: After his father's death Michael Gandolfini decided to pursue acting. He enrolled at New York University after graduating from high school. After early auditions, he was cast in the HBO drama series "The Deuce" as Joey Dwyer. In 2019, he was cast in "The Many Saints of Newark" to play the young version of Tony Soprano, the role played by his father in the television series "The Sopranos". Gandolfini had never watched the show. He described watching it while preparing for the role as an intense process. He was later cast in the Russo brothers’ crime drama "Cherry".


title: Ajay Devgn filmography

text: Ajay Devgn is an Indian actor, director and producer who works in Hindi films. He debuted as an actor in "Phool Aur Kaante" (1991), which won him the Filmfare Award for Best Male Debut. Devgn then played a kickboxer in the martial arts film "Jigar" (1992) and a blind in "Vijaypath" (1994). His subsequent hits include "Suhaag" (1994), "Dilwale" (1994), "Naajayaz" (1995), "Diljale" (1996), "Jaan" (1996), "Ishq" (1997), "Pyaar To Hona Hi Tha" (1998), and "Hum Dil De Chuke Sanam" (1999). He garnered Filmfare Best Actor nominations for "Naajayaz" and "Hum Dil De Chuke Sanam". His performance in "Zakhm" (1998) secured Devgn his first National Film Award for Best Actor. In 2000, Devgn started Ajay Devgn FFilms and produced and headlined the commercially unsuccessful "Raju Chacha". He got a Filmfare Best Supporting Actor nomination for enacting a dacoit in the ensemble film "Lajja" (2001).


title: Ajay Devgn filmography

text: 2002 proved to be a pioneer for Devgn as he received universal acclaim for his performances in "Company", "The Legend of Bhagat Singh" and "Deewangee". He won his second National Award for portraying revolutionary Bhagat Singh in "The Legend of Bhagat Singh" and received the Filmfare Critics Award for Best Actor for it and "Company". As the antagonist of "Deewangee", he earned a Filmfare Best Villain Award. His 2003 projects included "Bhoot", a sleeper hit, and "Gangaajal", in which he received another Filmfare Best Actor nomination for enacting a police officer. He next featured in "Yuva" (2004), "Kaal" (2005), and "Omkara" (2006). Rohit Shetty's "Golmaal" series established him in comic roles including "" (2006), "Golmaal Returns" (2008) and "Golmaal 3" (2010). Devgn was highly panned for "Aag" (2007), based on the 1975 cult classic "Sholay". "Aag" is considered one of the worst films. In 2008, he directed and produced "U Me Aur Hum". After featuring in "Sunday" (2008) and "" (2009), 2010 proved to be another milestone year for him as he delivered his first 100 Crore Club film with "Golmaal 3" and received positive feedback for his roles in the top-grossing films "Raajneeti" and "Once Upon a Time in Mumbaai". The latter fetched him a Filmfare Best Actor nomination, as like his next "Singham" (2011), the first part of Shetty's Cop Universe.


title: Ajay Devgn filmography

text: From the 2010s, Devgn shined to stardom with the successful comedies "Bol Bachchan" (2012), "Son of Sardaar" (2012), "Golmaal Again" (2017), "Total Dhamaal" (2019) and "De De Pyaar De" (2019) and the dramas "Drishyam" (2015) and "Raid" (2018). He reprised his role of Singham in Shetty's blockbuster films "Singham Returns" (2014), "Simmba" (2018) and "Sooryavanshi" (2021) and also directed, produced and starred in commercial failures like "Shivaay" (2016) and "Runway 34" (2022). He produced and starred as the eponymous warrior in "Tanhaji" (2020), winning his third National Best Actor Award. In 2022, he secured further critical and commercial success with the films "RRR", "Gangubai Kathiawadi" and "Drishyam 2". "Tanhaji", "RRR", "Drishyam 2" and "Golmaal Again" rank among the 200 Crore Club domestic net grossers.


title: Ajay Devgn filmography

text: He is next set to star "Bholaa, Maidaan, Raid 2, Singham 3, Golmaal 5" and an yet-untitled superhero big budget production by Yash Raj Films.


title: Markus Persson

text: Markus Alexej Persson (; born 1 June 1979), also known as Notch, is a Swedish video game programmer and designer. He is best known for creating the sandbox video game "Minecraft" and for founding the video game company Mojang in 2009.


title: Markus Persson

text: Persson's principal venture for founding Mojang was "Minecraft" which gained popularity and support since its tech demo in 2009. Since then, he has gained significant notability within the video game industry, winning multiple awards and establishing relations with the industry's figureheads. He retained his position as the lead designer of "Minecraft" until the game's official launch in 2011, after which he transferred creative authority to Jens Bergensten. He had continued to work on "Minecraft" until he left Mojang in September 2014, after its acquisition by Microsoft for $2.5 billion. Microsoft eventually dissociated from Persson following controversial comments regarding topics such as race and gender on his Twitter account.


title: Markus Persson

text: Persson was born in Stockholm, Sweden, to a Finnish mother and a Swedish father on 1 June 1979. He lived in Edsbyn for the first seven years of his life before his family moved back to Stockholm. He began programming on his father's Commodore 128 home computer at the age of seven. Having experimented with various type-in programs he produced his first game at the age of eight, a text-based adventure game. Professionally he had worked as a game developer for King for over four years, until 2009. Afterwards he worked as a programmer for Jalbum. He is also one of the founders of "Wurm Online", though he no longer works on it. Outside of work, he has made seven games for competitions. He is the central figure of "", a documentary by 2 Player Productions about the rise of "Minecraft" and Mojang.


title: Markus Persson

text: Persson is a member of the Swedish chapter of Mensa. In 2011, he married Elin Zetterstrand and had a daughter. On 15 August 2012, he announced that he and his wife had filed for divorce. The divorce was finalized later that year.


title: Markus Persson

text: Persson has criticized both piracy and the stance of large game companies on piracy; additionally, he is a member of the Pirate Party of Sweden. He is an atheist and has donated to Médecins Sans Frontières (Doctors Without Borders). Under his direction, Mojang contributed a week to developing "Catacomb Snatch" for the Humble Indie Bundle; the $458,248 raised was donated to charity.


title: Markus Persson

text: In December 2014, Persson purchased a home in Trousdale Estates, Beverly Hills, CA for $70 million, a record sales price for Beverly Hills at the time.


title: Markus Persson

text: Persson's most popular creation is the survival sandbox game "Minecraft", which was first publicly available on 17 May 2009 and fully released on 18 November 2011. Persson left his job as a game developer to work on "Minecraft" full-time until completion. In early 2011, Mojang AB sold the one millionth copy of the game, several months later their second, and several more their third. Mojang hired several new staff members for the "Minecraft" team, while Persson passed the lead developer role to Jens Bergensten. He stopped working on "Minecraft" after a deal with Microsoft to sell Mojang for $2.5 billion. This brought his net worth to US$1.5 billion.


title: Markus Persson

text: Persson and Jakob Porsér came up with the idea for "Scrolls" including elements from board games and collectible card games. Persson noted that he will not be actively involved in development of the game and that Porsér will be developing it. Persson revealed on his tumblr blog on 5 August 2011 that he was being sued by a Swedish law firm representing Bethesda Softworks over the trademarked name of "Scrolls", claiming that it conflicted with their "The Elder Scrolls" series of games. On 17 August 2011, Persson challenged Bethesda to a "Quake 3" tournament to decide the outcome of the naming dispute. On 27 September 2011, Persson confirmed that the lawsuit was going to court. ZeniMax Media, owner of Bethesda Softworks, announced the lawsuit's settlement in March 2012. The settlement allowed Mojang to continue using the Scrolls trademark.


title: Markus Persson

text: "Cliffhorse" is a humorous game programmed in two hours using the Unity game engine and free assets. The game took inspiration from ""s physics engine, "the more embarrassing minimum-effort Greenlight games", "Goat Simulator", and "". The game was released to Microsoft Windows systems as a honorware early access game the start day of E3 2014, instructing users to donate Dogecoin to "buy" the game before downloading it. The game accumulated over 280,000 dogecoins.


title: Markus Persson

text: Following the end to his involvement with "Minecraft", Persson began pre-production of an alternate reality space game set in the distant future in March 2012. On April Fools' Day, Mojang launched a satirical website for "Mars Effect" (parody of "Mass Effect"), citing the lawsuit with Bethesda as an inspiration. However, the gameplay elements remained true and on 4 April, Mojang revealed "0x10" (pronounced "Ten to the C") as a space sandbox title. Persson officially halted game production in August 2013. However, C418, the composer of the game's soundtrack (as well as that of "Minecraft"), released an album of the work he had made for the game.


title: Markus Persson

text: Persson has received criticism for political and social opinions he has expressed on social media since around 2017. Many of his comments have seen by others as misogynistic, racist, and homophobic. He claimed feminism was a "social disease", and called video game developer and feminism supporter Zoë Quinn a "cunt". He took offence to gay pride celebrations, asserting there should be heterosexual pride days and stating that opponents to his ideas "deserve to be shot". After facing backlash, he deleted the tweets and rescinded his statements, writing "So yeah, it's about pride of daring to express, not about pride of being who you are. I get it now." Persson said in social media that "It's okay to be white" and that he believed privilege is a "made up metric". He has promoted claims that people are fined for "using the wrong pronoun". Persson has also faced criticism for tweeting in support of QAnon, stating that "Q is legit. Don't trust the media."


title: Markus Persson

text: In March 2019, a "Minecraft" update removed all mentions of Persson from the game's menu, though his name is still in the credits. Microsoft did not explain this action, but its timing led multiple news outlets to conclude it was related to the controversies associated with him. Persson was not invited to the game's tenth anniversary event later in 2019, with Microsoft saying that his views "do not reflect those of Microsoft or Mojang".


title: Handjob

text: A handjob, also spelled hand job, is a sex act, performed as either foreplay or as non-penetrative sex, that involves the manual stimulation of the penis or scrotum by another person to induce an erection for sexual pleasure, sexual arousal and sometimes resulting in orgasm and ejaculation.


title: Handjob

text: A handjob can be sexually arousing for both participants and may be an erotic and physically intimate act of its own.


title: Handjob

text: A person may give a male partner a handjob so as not to engage in penetrative sexual activity. Besides avoiding the risks associated with sexual penetration, such as sexually transmitted infections (STIs) or pregnancy from penile-vaginal sex, some people engage in non-penetrative sex to preserve virginity.


title: Handjob

text: In some massage parlors, a masseuse, whether as part of the massage itself or directly after it, may perform a handjob on their customer; this is sometimes known by the euphemism "happy ending".


title: Handjob

text: An investigation by "Time Out New York" in January 2011 found many New York City massage parlors advertising "sensual massage" and providing handjobs. The parlors charged from $60 to $160, with an extra tip for the sex workers (usually $40) for a massage and manual "happy ending". Most of the massage parlors reviewed were "rub and tug joints" where handjobs were the only sexual services provided, and there was a strict policy of the male clients not touching the female workers.


title: Tron: Legacy

text: Tron: Legacy (stylized as TRON: Legacy) is a 2010 American science fiction action film directed by Joseph Kosinski (in his feature directorial debut) and written by Adam Horowitz and Edward Kitsis, from a story by Horowitz, Kitsis, Brian Klugman, and Lee Sternthal. It serves as a sequel to "Tron" (1982), whose director Steven Lisberger returned to produce. The cast includes Jeff Bridges and Bruce Boxleitner reprising their roles as Kevin Flynn and Alan Bradley, respectively, as well as Garrett Hedlund, Olivia Wilde, James Frain, Beau Garrett and Michael Sheen. The story follows Flynn's adult son Sam, who responds to a message from his long-lost father and is transported into a virtual reality called "the Grid," where Sam, his father, and the algorithm Quorra must stop the malevolent program Clu from invading the real world.


title: Tron: Legacy

text: Interest in creating a sequel to "Tron" arose after the film garnered a cult following. After much speculation, Walt Disney Pictures began a concerted effort in 2005 to devise "Tron: Legacy," with the hiring of Klugman and Sternthal as writers. Kosinski was recruited as director two years later. As he was not optimistic about Disney's "Matrix"-esque approach to the film, Kosinski filmed a high-concept, which he used to conceptualise the universe of "Tron: Legacy" and convince the studio to greenlight the film. Principal photography took place in Vancouver over 67 days, in and around the city's central business district. Most sequences were shot in 3D and ten companies were involved with the extensive visual effects work. Chroma keying and other techniques were used to allow more freedom in creating effects. Daft Punk composed the musical score, incorporating orchestral sounds with their trademark electronic music.


title: Tron: Legacy

text: "Tron: Legacy" premiered in Tokyo on November 30, 2010 and was theatrically released in North America on December 17, 2010. Disney vigorously promoted the film across multiple media platforms, including merchandising, consumer products, theme parks and advertising. Upon its release, the film received mixed reviews from film critics, who praised the visual effects, production design and , but criticized the character development, cast performance and story. The film grossed $400 million during its worldwide theatrical run against a $170 million production budget. The film was nominated for an Oscar for Best Sound Editing at the 83rd Academy Awards, but lost to "Inception". Like its predecessor, "Tron: Legacy" has also been described as a cult film.


title: Tron: Legacy

text: In 1989, Kevin Flynn, who was promoted to CEO of ENCOM International seven years earlier, disappears. Twenty years later, his son Sam, now ENCOM's primary shareholder, pranks the corporation by releasing the company's signature operating system online for free. ENCOM executive Alan Bradley, Flynn's old friend, approves of this, believing it aligns with Flynn's ideals of open software. Nonetheless, Sam is arrested for trespassing.


title: Tron: Legacy

text: Alan posts bail for Sam and tells him of a pager message originating from Flynn's shuttered video arcade. There Sam discovers a hidden basement with a large computer and laser, which suddenly digitizes and downloads him into the Grid, a virtual reality created by Flynn. He is captured and sent to "the Games", where he must fight a masked program named Rinzler. When Sam is injured and bleeds, Rinzler realizes Sam is human, or a "User". He takes Sam to Clu, the Grid's corrupt ruling program, who resembles a young Kevin.


title: Tron: Legacy

text: Clu nearly kills Sam in a Light Cycle match, but Sam is rescued by Quorra, an "apprentice" of Flynn, who shows him Flynn's hideout outside Clu's territory. Flynn explains that he had been working to create a "perfect" computer system and had appointed Clu and security program Tron as its co-creators. The trio discovered a species of naturally occurring "isomorphic algorithms" (ISOs), with the potential to resolve various natural mysteries. Clu, considering them an aberration, betrayed Flynn, killed Tron, and destroyed the ISOs. The "Portal" permitting travel between the two worlds closed, leaving Flynn trapped in the system. Clu sent the message to Alan hoping to lure him into the Grid (though Sam serves his purpose just as well) and reopen the Portal for a limited time. Since Flynn's "identity disc" is the master key to the Grid and the only way to traverse the Portal, Clu expects Sam to bring Flynn to the Portal so he can take Flynn's disc, go through the Portal himself, and impose his idea of perfection on the human world.


title: Tron: Legacy

text: Against his father's wishes, Sam returns to Clu's territory to find Zuse, a program who can provide safe passage to the Portal. At the End of Line Club, the owner reveals himself to be Zuse, then betrays Sam to Clu's guards. In the resulting fight, Flynn rescues his son, but Quorra is injured and Zuse gains possession of Flynn's disc. Zuse attempts to bargain with Clu over the disc, but Clu betrays him and destroys the club along with Zuse. Flynn and Sam stow away aboard a "Solar Sailer" transport program, where Kevin restores Quorra and reveals her to be the last surviving ISO.


title: Tron: Legacy

text: The transport is intercepted by Clu's warship. As a diversion, Quorra allows herself to be captured by Rinzler, whom Flynn recognizes as Tron, not killed by Clu but rather reprogrammed. Sam reclaims Flynn's disc and rescues Quorra, while Flynn takes control of a Light Fighter. Clu, Rinzler, and several guards pursue the trio in Light Jets. Rinzler remembers his past as Tron and deliberately collides with Clu's Light Jet, then falls into the Sea of Simulation below. Clu confronts the others at the Portal, where Flynn reintegrates with his digital duplicate, destroying Clu along with himself, while Quorra - having switched discs with Flynn - gives Flynn's disc to Sam and they escape together to the real world as the resulting explosion levels the Sea of Simulation. In Flynn's arcade, Sam backs up and deactivates the system. He then tells a waiting Alan that he plans to retake control of ENCOM, naming Alan chairman of the board. Sam departs on his motorcycle with Quorra, and she witnesses her first real sunrise.


title: Tron: Legacy

text: Beau Garrett appears as Gem, one of four programs known as Sirens. The Sirens operate the Grid's game armory, equipping combatants with the armor needed to compete in the games, while also reporting to Castor. Serinda Swan, Yaya DaCosta, and Elizabeth Mathis depict the other three Sirens. Jeffrey Nordling stars as Richard Mackey, the chairman of ENCOM's executive board, and Cillian Murphy makes an uncredited appearance as Edward Dillinger, Jr., the head of ENCOM's software design team and the son of former ENCOM Senior Executive Ed Dillinger portrayed by David Warner in the original film.<ref name="http://blogs.indiewire.com/theplaylist/which_actor_makes_a_surprise_cameo_in_tron_legacy_and_is_maybe_set_up_as_a_"></ref> Daft Punk, who composed the score for the film, cameo as disc jockey programs at Castor's End of Line Club, and "Tron" creator Steven Lisberger makes an appearance as Shaddix, a bartender in the End of Line Club.


title: Tron: Legacy

text: Steven Lisberger relocated to Boston, Massachusetts from Philadelphia, Pennsylvania in the 1970s to pursue a career in computer animation. Since the computer animation field was mainly concentrated in Los Angeles, Lisberger had very little competition operating on the East Coast: "Nobody back then did Hollywood stuff, so there was no competition and no one telling us that we couldn't do it." He later produced and directed the American science fiction film "Tron" (1982) for Walt Disney Productions, the first computer animation-based feature film. Although the film garnered some critical praise, it generated only modest sales at the box office — the cumulative North American gross was just $33 million. Producer Sean Bailey, who saw the film with his father and Lisberger, was captivated by the finished product. Although "Tron" performed below Disney studio's expectations, it later developed a cult following, which fueled speculation of Pixar's alleged interest in creating a sequel, in 1999. Rumors of a "Tron" sequel were further ignited after the 2003 release of the first-person shooter video game, "Tron 2.0". Lisberger hinted that a third installment could be in the works, depending on the commercial success of the game.


title: Tron: Legacy

text: Shortly after hiring Kosinski, Bailey approached screenwriting duo Adam Horowitz and Edward Kitsis, who accepted for being self-described "obsessed about "Tron"." Horowitz later claimed the challenge was to "homage the first movie, continue the story, expand it and take it to another place and open up space for new fans," and Kitsis claimed that the film would start a whole new mythology "of which we're only scratching the surface." Horowitz and Kitsis first created a story outline, and developed and fine-tuned the plot with Bailey and Kosinski across a period of two days in La Quinta. The writers also consulted Lisberger, to view "Tron"s creator input on the story. Lisberger gave his blessing, particularly as he has a son the same age as Sam, which Kitsis stated that "was like we had tapped into something he was feeling without even realizing it." The Pixar team contributed with rewrites for additional shooting after being shown a rough cut in March 2010, which helped in particular to the development of Sam's story line.


title: Tron: Legacy

text: The writing staff cited "The Wizard of Oz" as a source of thematic influence for "Tron: Legacy" in writing the script, with Kitsis stating that "They both have very similar DNA, which is "Tron" really lives on, in a lot of ways, trying to get home. You're put on this world and you want to go home and what is home? That's in a lot of way inspired us." Kitsis also added that they had to include an "emotional spine to take us into the story or else it just becomes a bunch of moves or gags and stuff," eventually deciding on adding a mysterious destiny to Flynn and giving him a legendary aura - "Kevin Flynn to us was Steve Jobs and Bill Gates all wrapped up into one and John Lennon." The writers decided to create the character of Clu as an evil embodiment of "how you look back on your younger self, (...) that guy [that] thought he knew everything, but he really knew nothing." Bridges liked the idea of the dual perspectives, and contributed with the writers for the characterization of Flynn as a sanguine Zen master by suggesting them to get inspiration from various Buddhist texts. Part of the concepts emerged from a reunion the producers had with scientists from California Institute of Technology and the Jet Propulsion Laboratory to discuss concepts such as isomorphic algorithms and the digitizing of organic matter.


title: Tron: Legacy

text: Horowitz revealed the film would contain many light cycle battles, and asserted that the script for the scenes were "incredibly detailed," and involved an intricate collaborative process. For the disc game, Horowitz and Kitsis wrote a rough draft of the scene, and sent the script to Kosinski; he summarized his perspective of the sequence's visuals to them. "He described them as these underlying platforms," said Horowitz, "that would then coalesce and then the way you would go from round to round in the game is you defeat someone, they kinda come together as you see in the movie." After giving his intake, Kosinski sent various sketches of the scene to the writers and would often revise the script. Kitsis thought that illustrating the character's stories to be the most difficult task in writing "Tron: Legacy". The writers collaborated with the creative process throughout production, which was helpful especially considering the difficulties of describing in a tangible way a digital world that "in its very nature defies basic screenwriting conventions."


title: Tron: Legacy

text: Plans for creating "Tron: Legacy" began to materialize in 2005, when Walt Disney Studios hired screenwriters Brian Klugman and Lee Sternthal as writers for the film. The two had recently finished writing the script for "Warrior". According to "Variety" columnist Michael Fleming, Klugman and Sternthal felt "that the world has caught up to Lisberger's original concept." Klugman said of the precedent film: "It was remembered not only for story, but a visual style that nobody had ever used before. We are contemporizing it, taking ideas that were ahead of the curve and applying them to the present, and we feel the film has a chance to resonate to a younger audience."


title: Tron: Legacy

text: In 2007, Disney began to negotiate with Joseph Kosinski to direct "Tron: Legacy". Kosinski admitted that at the time, he was not keen on the idea but it later grew on him as time progressed. Kosinski was involved in a meeting with Bailey, president of Walt Disney Pictures. "Disney owns the property, "Tron"," Bailey stated. "Do you know it? Are you interested? What would your take be? In a post-"Matrix" world, how do you go back to the world of "Tron"?" Kosinski wanted to embrace the general ambiance of the film and wished to not use the Internet as a model or use a formula emulative of "The Matrix" film series. As neither individuals were in equal agreement on choosing a perspective to conceive the film, Kosinski asked Bailey to lend him money in order to create a conceptual prototype of the "Tron: Legacy" universe, which was eventually presented at the 2009 San Diego Comic-Con International. "So, we went into Disney," he recalled, "and I told them, 'We can talk about this all day, but in order to really get on the same page, I need to show you what this world looks and feels like. Give me some money and let me do a small test that will give you a hint for a couple minutes of it, and see what you think.'"


title: Tron: Legacy

text: A graduate of Columbia University architecture school, Kosinski's knowledge of architecture was pivotal in conceptualizing the "Tron: Legacy" universe. His approach in cultivating a prototype was different from other film directors because, according to Kosinski, he came "from a design point of view"; "Some of my favorite directors come from outside of the film business, so that made my approach different from other directors, but a design background makes sense for a movie like this because the whole world has to be made from scratch." Lisberger would later state that he left the sequel to a different production team because "after thirty years I don't want to compete with myself," and to showcase how the next generation dealt with the themes contained in "Tron" - "If I brought my network in, it would be a little bit like one of those Clint Eastwood movies where all the old guys go to space." Lisberger added that "I dig this role of being the Obi-Wan or the Yoda on this film more than being the guy in the trenches," stating that unlike Kosinski his age was a hindering factor - "I cannot work sixteen hours a day staring at twenty-five monitors for most of that time."


title: Tron: Legacy

text: "Tron: Legacy" is imbued with several references to religious themes, particularly those relating to Christianity and Buddhism. Olivia Wilde's character, Quorra, was inspired/formed by the historical Catholic figure Joan of Arc. Wilde sought inspiration from her six months before production of the film commenced. She, alongside Kosinski, collaborated with the writers on editing the characters so she would contain the characteristics of Joan of Arc. Wilde assessed the characteristics of the figure: "She's this unlikely warrior, very strong but compassionate, and completely led by selflessness. Also, she thinks she's in touch with some higher power and has one foot in another world. All of these were elements of Quorra." Since she epitomizes the concept of androgyny, producers conceived Quorra from an androgynous perspective, notably giving her a short haircut.


title: Tron: Legacy

text: Bridges opined that "Tron: Legacy" was evocative of a modern myth, adding that ideas alluding to technological advancement were prevalent throughout the film. To Cyriaque Lamar of io9, the film's approach to technology was reminiscent of a kōan. "One of the things that brought me to this film," affirmed Bridges, "was the idea of helping to create a modern-day myth to help us navigate through these technological waters [...]. I dig immediate gratification as much as anybody, but it happens so fast that if you make a decision like that, you can go far down the wrong path. Think about those plastic single-use water bottles. Where did that come from? Who decided that? You can have a couple of swigs of water [...] and those bottles don't disintegrate entirely. Microscopic animals eat the plastic, and the fish eat those, and we're all connected. It's a finite situation here."


title: Tron: Legacy

text: According to screenwriter Adam Horowitz, Kosinski stated that the film's universal theme was "finding a human connection in a digital world." They followed this by "approach[ing] the world from the perspective of character, using Kevin Flynn as an organizing principle, and focus on the emotional relationship from father and son and their reconciliation, which brings profound turns in their respective individual lives."


title: Tron: Legacy

text: At the 2008 San Diego Comic-Con, a preliminary teaser trailer (labeled as "TR2N" and directed by Joseph Kosinski) was shown as a surprise to convention guests. It depicted a yellow Program engaged in a light cycle battle with a blue Program, and it prominently featured Jeff Bridges reprising his role as an aged Kevin Flynn (from the first film). At the end of the trailer, the yellow Program showed his face, which appeared identical to Flynn's earlier program Clu (resembling the younger Flynn in "Tron").


title: Tron: Legacy

text: While the trailer did not confirm that a "Tron" sequel was in production, it showed that Disney was serious about a sequel. In an interview with Sci-Fi Wire, Bridges revealed that the test footage was unlikely to appear in the finished film. On July 23, 2009, Disney revealed film's title at their panel at Comic-Con. Bridges explained that the title is in reference to the story's theme: "It's basically a story about a son's search for his father." They also showed a trailer similar to the one shown at Comic-Con 2009, with updated visuals. At the time, the film had just wrapped production and they had a year of post-production ahead of them. Because none of the footage from inside the computer world was finished, they premiered concept images from the production. Art included the Recognizer, which has been updated from the original film. Concept photos were also shown of Disc Wars, which has also been revised from the original film into a 16-game tournament. The arena is set up so that the game court organically changes, and all 16 games are going on at the same time. The boards also combine in real time until the last two Disc warriors are connected.


title: Tron: Legacy

text: Light cycles make a return, with new designs by Daniel Simon. According to the press conference at Comic-Con 2008, a new vehicle appears called a "Light Runner," a two-seat version of the light cycle, and Kevin Flynn's own cycle, a "Second Generation Light Cycle" designed in 1989 by Flynn and is "still the fastest thing on The Grid." It incorporates some of the look of both films.


title: Tron: Legacy

text: A life-size model of the light cycle was put on display at a booth at Fan Expo 2009 in Toronto, Ontario from August 28–30, 2009, along with a special presentation of material from the production. The conceptual art shown at Comic-Con was shown in the session, along with some test film of the martial artists who play a more athletic style of Disc Wars. A segment from the film showed Flynn's son entering the now-decrepit arcade, playing a "Tron" stand-up arcade video game, noticing a passage in the wall behind the "Tron" game and entering it, the passage closing behind him. Flynn's son makes the visit to the arcade after Alan Bradley receives a page from the disconnected phone number of the arcade. The footage was used later as part of the trailer released on March 5, 2010.


title: Tron: Legacy

text: The character of Yori and her user, Dr. Lora Baines, do not appear in the sequel, even though the film refers to Alan Bradley being married to Lora. Fans have lobbied for actress Cindy Morgan to be in the film with active campaigns online, such as "Yori Lives" on Facebook, which is independent of Morgan herself. "All I know is what I'm seeing online," Morgan said. "I am so thrilled and touched and excited about the fan reaction and about people talking about the first one and how it relates to the second one. I can't tell you how warm a feeling I get from that. It just means so much." No one from "Tron: Legacy" had contacted Morgan, and she did not directly speak with anyone from the sequel's cast and crew. As Dr. Lora Baines, Cindy Morgan had appeared with Bruce Boxleitner (as Alan Bradley) at the Encom Press Conference in San Francisco, April 2, 2010.


title: Tron: Legacy

text: Principal photography took place in Vancouver, British Columbia in April 2009,<ref name="http://www.firstshowing.net/2009/disneys-tron-2-also-going-to-cost-300-million-to-make/"></ref> and lasted for approximately 67 days. Many filming locations were established in Downtown Vancouver and its surroundings. Stage shooting for the film took place at the Canadian Motion Picture Park studio in Burnaby, an adjacent city that forms part of Metro Vancouver. Kosinski devised and constructed twelve to fifteen of the film's sets, including Kevin Flynn's safe house, a creation he illustrated on a napkin for a visual effects test. "I wanted to build as much as possible. It was important to me that this world feel real, and anytime I could build something I did. So I hired guys that I went to architecture school with to work on the sets for this film, and hopefully people who watch the film feel like there's a certain physicality to this world that hopefully they appreciate, knowing that real architects actually put this whole thing together." The film was shot in dual camera 3D using Pace Fusion rigs like James Cameron's "Avatar", but unlike the Sony F950 cameras on that film, "Tron" used the F35s. "The benefit of [the F35s]," according to director Kosinski, "is that it has a full 35mm sensor which gives you that beautiful cinematic shallow depth of field." The film's beginning portions were shot in 2D, while forty minutes of the film were vertically enhanced for IMAX. Digital Domain was contracted to work on the visual effects, while companies such as Prime Focus Group, DD Vancouver, and Mr. X were brought on to collaborate with producer on the post-production junctures of "Tron: Legacy". Post-production wrapped on November 25, 2009.


title: Tron: Legacy

text: The sequences on the Grid were wholly shot in 3D, utilizing cameras specifically designed for it, and employed a 3D technique that combined other special effects techniques. The real-world sequences were filmed in 2D, and eventually altered using the three-dimensional element. Bailey stated that it was a challenge shooting "Tron: Legacy" in 3D because the cameras were bigger and heavier, and variations needed to be taken into account. Despite these concerns, he opined that it was a "great reason to go to the movies because it's an experience you just can't recreate on an iPhone or a laptop." In some sequences the image shows a fine mesh pattern and some blurring. That is not interference or a production fault, but indicates that that sequence is a flashback and to simulate an older form of video representation technology. Stunt work on the film was designed and coordinated by 87Eleven, who also designed and trained fight sequences for "300" and "Watchmen". Olivia Wilde described it as an honor to train with them.