Why are anions larger than their parent atom?

1 Answer
Mar 1, 2016

By definition, an anion is a negatively charged atom.


By nature, atoms are neutral in charge, as there are the same number of negative charges (electrons) as positive charges (protons). However, in compounds (mixes) called ionic compounds, an electron leaves one atom and joins another. This forms what is known as an ion. An ion can either be charged negatively, which gives it the name anion, or can be charged positively, which gives it the name cation.

An anion gains an electron, making it larger than its mother atom. A cation, on the other hand, loses one of its electrons, making it smaller. Don't forget that the number of protons is a fixed amount depending on the element: it's the number of electrons that can change.

Practice exercises:

  1. Explain what is an ionic compound.

Good luck!