What is the electron configuration of Ca+2?

1 Answer
Nov 2, 2015

The electron configuration of a #"Ca"^(2+)"# ion is #"1s"^2"2s"^2"2p"^6"3s"^2"3p"^6"#.

Explanation:

The atomic number of calcium is 20. This means that in a neutral calcium atom, there are 20 protons in its nucleus. A neutral calcium atom also has 20 electrons. The electron configuration of a neutral calcium atom is #"1s"^2"2s"^2"2p"^6"3s"^2"3p"^6"4s"^2"#.

A calcium #2+# ion has lost its two valence electrons, and now has #18# electrons. The electron configuration of a #"Ca"^(2+)"# ion is #"1s"^2"2s"^2"2p"^6"3s"^2"3p"^6"#, which is isoelectronic with the noble gas argon.