when do you use four periods in an ellipsis
Ellipsis Whether an ellipsis at the end of a sentence needs a fourth dot to finish the sentence is a matter of debate; Chicago advises it,[4] as does the Publication Manual of the American Psychological Association (APA style),[5], while some other style guides do not;[citation needed] the Merriam-Webster Dictionary and related works treat this style as optional, saying that it "may" be used.[6] More commonly, a normal full stop (period) terminates the sentence, then a separate three-dot ellipsis is used to indicate one or more subsequent elided sentences before continuing a longer quotation. Business Insider magazine suggests this style,[7] and it is also used in many academic journals. Even the Associated Press Stylebook[8] – notably hostile to punctuation that journalists may consider optional and removable to save newsprint column width – favors this approach. It is consistent in intent if not exact form with the agreement among those in favor of a fused four-dot ellipsis that the first of them is a full stop terminating the sentence and the other three are the ellipsis.
Period 1 element A period 1 element is one of the chemical elements in the first row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate periodic (recurring) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements with similar behaviour fall into the same vertical columns. The first period contains fewer elements than any other row in the table, with only two: hydrogen and helium. This situation can be explained by modern theories of atomic structure. In a quantum mechanical description of atomic structure, this period corresponds to the filling of the 1s orbital. Period 1 elements obey the duet rule in that they need two electrons to complete their valence shell. The maximum number of electrons that these elements can accommodate is two, both in the 1s orbital. Therefore, period 1 can have only two elements.