Question

Arrange these ions in order of increasing ionic radius: P3-, N3-, Cl-, In3+

Answer 1

The more an atom gains electrons, the more the ionic radius increases and the more it loses electrons, the ionic radius decreases. Meaning, the smallest one is the positively charged one, because it lost electrons, in this case In3+, followed by Cl-, then N3- and finally p-3.P-3 came after N-3, because of a trend down the group: the atomic radius increases, therefore P gaining the same number of electrons as N, P will always be larger in size.