Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?

Explanation

The sum .(IE)_(k)+(EE)_(2). increases. As a. result, the standurd reduction potentiak .(E)^(0). becomes less and less negative. Hence, the tendency:to form .(M)^(2 ion decreases. The greater stability of +2 staite for .(Mn). is due to half-filled d-subshelt. .(3 (~d)^(5) . (So)., the first member-of the first transition series-is having olectronte contiguration of .3 d^(prime) 4 s^(*).. It will prefer to lose all the three.electronis to form Argon core. There fore, it prefers to show an oxidation .state. of +3 more than +2