In the d-block elements as we move along a period the atomic radius decreases in the beginning, reaches minimum and then increases towards the end of the series. Explain with appropriate reasons.

In the d-block elements as we move along a period the atomic radius d

1.	In the d-block elements as we move along a period the atomic radius decreases in the beginning, reaches minimum and then increases towards the end of the series. Explain with appropriate reasons.
Answer» Solution :In a particular series of d-block elements, electron filling TAKES place in the penultimate shell. HENCE their atomic size decreascs up to the `7^(th)` group and reaches minimum and then again increases because with the pairing of electrons, repulsive FORCE also increases. The repulsion among the added electrons exceeds the increased force of attraction (due to the increase of nuclear charge) after the `8^(th)` group. Hence, atomic radius increases slightly.