(1) Na+, Mg2+ and Al3+ are all isoelectronic
(2) Ionic radius of K+ is larger than that of Cl− even though they are isoelectronic
(3) Anions are always larger than the neutral atoms from which they are derived
(4) Cations are always larger than the neutral atoms from which they are derived
Only (2) is incorrect.(2) and (4) are incorrect(1), (2) and (3) are incorrect(1), (3) and (4) are incorrect