# how to find valency of calcium using spdf electronic configuration [closed]

Electronic configuration of calcium is $\ce{1s^2 2s^2 2p^6 3s^2 3p^6 4s^2}$. The orbitals are fully filled with electrons so would its valency be two or zero?

• The configuration $$1s^2 2s^2 2p^6 3s^2 3p^6 4s^2$$ has a valency of zero since there are as many electrons as protons. The configuration $$1s^2 2s^2 2p^6 3s^2 3p^6$$ is two electrons short, so it has a valency of +2. – MaxW Dec 17 '15 at 15:34