Question

Explain the trend in an Oxidation state of 3d elements.

Answer 1

Trends in oxidation state of 3d elements:

1. One of the notable features of transition elements is the great variety of oxidation states they show in their compounds.
2. Loss of 4s and 3d electrons progressively leads to formation of ions. The transition elements display a variety of oxidation states in their compounds. Loss of one 4s electron leads to the formation of M⁺ ion, loss of two 4s electrons gives a M²⁺ ion while loss of unpaired 3d and 4s electrons gives M³⁺, M⁴⁺ ions and so on.
3. As the number of unpaired electrons in 3d orbitals increases, the number of oxidation states shown by the element also increases. Scandium has only one unpaired electron. It shows two oxidation states while manganese with 5 unpaired d electrons shows six different oxidation states.
4. The elements which give the greatest number of oxidation states occur in or near the middle of the series. Manganese, for example, shows oxidation states from +2 to +7.