Question

In group 13, Boron to Aluminium size increases but from Aluminium to Gallium size decreases. why??​

Answer 1

Atomic radius of gallium is less than aluminium. ... The atomic radiusof 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.

Answer 2

ANSWER

top 13 from Boron to Aluminium atomic size increases. but from aluminium to gallium, atomic size decreases because of poor shielding effect of electrons in 3D orbital of Gallium .

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