A zwitterion is a molecule containing an equal number of functional group(s) charged positively and of functional group(s) charged negatively. Zwitterions may also be called internal salts. With amino acids, for example, a chemical equilibrium between the "parent" molecule and the zwitterion will be formed in solution. Betaines are zwitterions that cannot isomerize to an all-neutral form, for instance when the positive charge is on a quaternary ammonium group. Likewise, a molecule that comprises a group of phosphoniums and a group of carboxylate cannot isomerise. Although the equilibrium cannot be experimentally studied in solution between a compound and its zwitterion isomer, some knowledge can be obtained from the results of theoretical calculations. Comment your views through Email: chemengineerapp@scitecjournals.com We are accepting Submission regarding the chemistry field directly online https://www.scitechnol.com/submission/ For more information check our website https://www.scitechnol.com/ you can also apply for membership or subscription.