Question

Write the electron configuration for the following elements in the ground state.

1. P and P3- (atomic number =15).
2. Ca and Ca2+ (atomic number =20).

Answer 1

1. $P\rightarrow 1s^2,2s^2,2p^6,3s^2,3p^3$

$P^{3+}\rightarrow 1s^2,2s^2,2p^6,3s^2$

2.$Ca \rightarrow 1s^2,2s^2,2p^6,3s^2,3p^6,4s^2$

$Ca^{2+}\rightarrow 1s^2,2s^2,2p^6,3s^2,3p^6$