What is meant by inert pair effect? explain.
The inert-pair effect refers to the empirical observation that the heavier elements of groups 13–17 often have oxidation states that are lower by 2 than the maximum predicted for their group. For example, although an oxidation state of +3 is common for group 13 elements, the heaviest element in Group 13, thallium (Tl), is more likely to form compounds in which it has a +1 oxidation state.
The inert pair effect says that the ns2ns2 valence electrons of metallic elements, especially the 5s2 5s2 and 6s2 6s2 pairs that follow the second and third row of transition metals, are less reactive than would be expected based on periodic trends such as effective nuclear charge, atomic sizes, and ionization energies. In, Tl, Sn, Pb, Sb, Bi, and, To some extent, Po do not always show their expected maximum oxidation states. Rather, sometimes they form compounds in which their oxidation states are 2 less than what would be expected.
There appear to be two major reasons for the inert-pair effect:
- increasing ionization energies and
- decreasing bond strengths.
The inert-pair effect refers to the empirical observation that the heavier elements of groups 13–17 often have oxidation states that are lower by 2 than the maximum predicted for their group. For example, although an oxidation state of +3 is common for group 13 elements, the heaviest element in Group 13, thallium (Tl), is more likely to form compounds in which it has a +1 oxidation state.
The inert pair effect says that the ns2ns2 valence electrons of metallic elements, especially the 5s2 5s2 and 6s2 6s2 pairs that follow the second and third row of transition metals, are less reactive than would be expected based on periodic trends such as effective nuclear charge, atomic sizes, and ionization energies. In, Tl, Sn, Pb, Sb, Bi, and, To some extent, Po do not always show their expected maximum oxidation states. Rather, sometimes they form compounds in which their oxidation states are 2 less than what would be expected.
There appear to be two major reasons for the inert-pair effect:
- increasing ionization energies and
- decreasing bond strengths.
