Question

Which pair below is isoelectronic?

Answer 1

\[1. Ca ^{+2} & Mg ^{+2} 2. Cl ^{-} & S 3. P ^{-3} & K ^{+} 4. Fe ^{+3} & Fe ^{+2}\]

Answer 2

Isoelectronic = same valence electron configuration

Answer 3

so do the Noble gases have to match? or just the Valence part?

Answer 4

the valence