Question

Which ion with a charge of -2 has an electron configuration of 1s22s22p6?

Answer 1

Answer:

O²-

Explanation:

The configuration is 1s² 2s² 2p6 with charge = -2

So, it means that 2 more electrons are added. If we subtract these two electrons we will get the configuration of the element in neutral state.

Therefore the new configuration would be 1s² 2s² 2p4. This has a total of 8 electrons and is neutral. This means that atomic number = No. of protons = No. of electrons = 8.

The element with 8 electrons is Oxygen.

∴ Ion is O²-

Hope this helps! :)