Encyclopedia

cation

cation (kăt"ī'un) [key], atom or group of atoms carrying a positive charge. The charge results because there are more protons than electrons in the cation. Cations can be formed from a metal by oxidation (see oxidation and reduction), from a neutral base (see acids and bases) by protonation, or from a polar compound by ionization. Cationic species include Na+, Mg++, and NH4+. The cations of the transition elements have characteristic colors in water solution. Salts are made up of cations and anions. See ion.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2007, Columbia University Press. All rights reserved.

More on cation from Fact Monster:

  • alum - alum alum , any one of a series of isomorphous double salts that are hydrated sulfates of a ...
  • ion, in chemistry: Positive and Negative Electric Charges - Positive and Negative Electric Charges A neutral atom or group of atoms becomes an ion by gaining ...
  • anion - anion anion , atom or group of atoms carrying a negative charge. The charge results because there ...
  • valence, in chemistry: Valence Number - Valence Number Atoms are assigned numbers, called valence numbers, oxidation numbers, or oxidation ...
  • isomorphism - isomorphism isomorphism , of minerals, similarity of crystal structure between two or more distinct ...

See more Encyclopedia articles on: Chemistry: General