text: <unk>  involves the passage of an electric current through, in general, an ionic substance that is either molten or dissolved in an aqueous solution resulting in chemical reactions at the electrodes. The negative electrode is called the cathode, and the positive electrode is the anode. 
  An ionic compound is dissolved with an appropriate solvent, or melted by heat, so that its ions are available in the liquid. An electrical current is applied between a pair of inert electrodes immersed in the liquid. 
  Each electrode attracts ions that are of the opposite charge. Therefore, positively-charged ions (called cations) move towards the cathode, whereas negatively-charged ions (termed anions) move toward the anode. The energy required to separate the ions, and cause them to gather at the respective electrodes, is provided by an electrical power supply. At the probes, electrons are absorbed or released by the ions, forming a collection of the desired element or compound.
  Oxidation of anions can take place at the anode, and the reduction of cations at the cathode. For example, it is possible to oxidize cations at the anode:
  It is also possible to reduce anions at the cathode:
  Neutral molecules can also react at either electrode. For example:
  File:P-Benzoquinone.svg 
  +
   
  2
  e
  −
  +
   
  2
  H
  +
  ⟶
   
  {\displaystyle \mathrm {+\ 2e^{-}+\ 2H^{+}\longrightarrow \ } }
  The following technologies are related to<unk> :
  Electrochemical cells, including the hydrogen fuel cell, use the reverse of this process.
  Gel electrophoresis is an<unk>  wherein the solvent is a gel: It is used to separate substances, such as DNA strands, based on their electrical charge.
option_0: Electrolysis
option_1: Sterilization 
option_2: Hydrogenation
option_3: Solution
option_4: Hydrolysis
option_5: Vapor-liquid equilibrium
option_6: Flux 
option_7: Adsorption