Which of the following pairs has almost the same atomic radii? — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

The electronic configuration of Aluminum (Al) is 2 2 6 2 1 1s 2s 2p 3s 3p The electronic configuration of Gallium (Ga) is 2 10 1 Ar 4s 3d 4p The atomic radius of aluminium and gallium is almost the same due to the poor shielding effect of d-orbitals present in gallium. Poor shielding effect of d-orbitals increases the effective nuclear charge on the outermost electrons which results in a reduction in atomic size.