Considering only ions with charges of +1, +2, -1 and -2, or neutral atoms, give the symbols for 4 species that are isoelectronic with the sulfide ion, S2-

Answer 1

First, let's look at the electron configuration of the sulfide ion, S2-. We start with neutral S which is 1s²2s²2p⁶3s²3p⁴. Now we remove add 2 valence electrons to make S2- and we get 1s²2s²2p⁶3s²3p⁶.

Note that this ion has 18 electrons. Species (+1,+2.-1,-1 and neutral) that are isoelectronic with this sulfide ion are...

Cl^-, Ar, K⁺ and Ca²⁺.