Ca 2+ Electron Configuration (Calcium Ion)

In this video we will write the electron configuration for Ca2+, the Calcium ion. We’ll also look at why Calcium forms a 2+ ion and how the electron configuration for Ca2+ is similar to the Nobel gas Krypton. Note: At 1:46 I incorrectly say that the Ca 2+ would have the same electron configuration as Kr. It should be Argon (Ar). The key idea is that it obtains the same general configuration of a Nobel gas. To begin with, Calcium (Ca) has an electronic configuration of 1s22s22p63s23p64s2 . To learn more about writing electron configurations see: When Calcium forms an ion it loses its two valence electrons. Since electrons are negative, losing two results electrons results in Ca having a 2+ charge. To write the electron config all we have to do is remove two electrons from the configuration for Ca (the 4s2 where 4 is the energy level and 2 represents the number of electrons). That leaves us with: 1s22s22p63s23p6 And that is the electron configuration for Ca2+ , the calcium ion.