Write the electron configuration for $Ca^+$ . (Express your answer as a series of orbitals, in order of increasing orbital energy. For example, the electron configuration of Li would be entered as 1s22s1 or [He]2s1.) Write the electron configuration for $Ca^{2+}$ . (Express your answer as a series of orbitals, in order of increasing orbital energy. For example, the electron configuration of Li would be entered as 1s22s1 or [He]2s1.) Write the electron configuration for $Se^{2-}$ . (Express your answer as a series of orbitals, in order of increasing orbital energy. For example, the electron configuration of Li would be entered as 1s22s1 or [He]2s1.) Write the electron configuration for $S^{2-}$ . (Express your answer as a series of orbitals, in order of increasing orbital energy. For example, the electron configuration of Li would be entered as 1s22s1 or [He]2s1.)

Answer:

$Ca^+:19:[Ar]4s^1$

$Ca^{2+}:18:[Ar]$

$Se^{2-}:32:[Ar]3d^{10}4s^24p^2$

$S^{2-}:18:[Ar]$

Explanation:

Electronic configuration represents the total number of electrons that a neutral element contains. We add all the superscripts to know the number of electrons in an atom.

The electrons are filled according to Afbau's rule in order of increasing energies. The positively charged species are formed by loss of electrons and negatively charged species are formed by gain of electrons.

$Ca:20:[Ar]4s^2$