Which of the following species are isoelectronic? Select all that apply.

Question

1) S^2-
2) Be^2+
3) Cl^-
4) K^+
5) Ca^2+
6) Se^2-

Answer 1

Answered below.

Answer 2

So far I have S^2-, Cl^-, K^+, and Ca^2+ instead the other two as the answer. Please tell me if I have these answers correct.