Question

Why does the radius of gallium is less than that of aluminium?

Answer 1

Atomic radius of gallium is less than aluminium. ... The atomic radius of the Ga is less than Al because of poor screening effect. Theatomic radius of Ga is slightly lesser than of Al because in going from Al to Ga, the electrons have already occupied 3d sub shell in Ga

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Answer 2

Answer:

Gallium has smaller atomic radius than aluminium because the d orbital which is highly diffused offers poor shielding effect which results in increased nuclear charge. Due to increased charge by nucleus, outer electrons get attracted, decreasing the radius.