I(a) (i) Atomic radius of M is smaller than that of X. The effective nuclear charger in M is greater than in X hence outer electrons strongly pulled to the centre reducing the radius.
(ii) Radius of Q is greater than that of U because Q has more energy levels than U
(b) J because it loses energy more easily due to the bigger atomic radius of J
marto answered the question on October 1, 2019 at 07:12
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