Which ion with a charge of -2 has an electron configuration of #1s^2 2s^2 2p^6#?

1 Answer
Nov 14, 2015

Answer:

If there are 10 electrons in total and a formal negative charge of #-2#, there must be 8 positive charges in the nucleus.

Explanation:

Since #Z# #=# #8#. the identity of this nucleus must be oxygen. Note that you will never sit a Chemistry or Physics exam without access to a Periodic Table. You must have this, and if you don't raise merry hell.