Why do transition elements show variable states ? How is the variability in oxidation states of d-block different from that of the p-block elements?
Answers
Explanation:
1.Transition elements show variable state oxidation in their compounds because there is a very small energy difference in between (n-1)d and ns orbitals. As a result, electrons of (n-1)d orbitals as well as ns-orbitals take part in bond formation.
2. Mn(Z-25) has the maximum number of unpaired electrons present in the d-subshell so it shows maximum oxidation states(+7)
3. Sc only exhibits a +3 oxidation state in these series.
4.The lanthanide contraction, i.e. the reduction in size of the Ln^{3+}Ln
3+
ion from La^{3+}La
3+
(103 pm) to Lu^{3+}Lu
3+
(86.1 pm), is often explained by the poor shielding of the 5s and 5p electrons by the 4f electrons.An alloy is a solid solution of two or more elements in a metallic matrix. It can either be a partial solid solution or a complete solid solution. Alloys are usually found to possess different physical properties than those of the component elements.An important alloy of lanthanoids is Mischmetal. It contains lanthanoids (94−95%), iron (5%), and traces of S, C, Si, Ca, and Al.