Why do transition metals show a number of oxidation states ? Explain. 

Why do transition elements show variable oxidation state?

Explain the following (a) Zr and Hf exhibit similar properties. (b) Most of the transition elements show large number of oxidation states.

Which of the 3d series of the transition metals exhibits the largest number of oxidation states and why?

(a) Why do transition elements show variable oxidation states? (i) Name the element showing maximum number of oxidation states among the first series of transition metals from Sc (Z = 21) to Zn (Z = 30). (ii) Name the element which shows only + 3 oxidation state. (b) What is lanthanoid contraction? Name an important alloy which contains some of the lanthanoid metals.

Why do alkali metals not show variable oxidation states ?

In which of the following compounds transition metal has zero oxidation state ?

(i) Name the element of 3d transition series which shows maximum number of oxidation states. Why does it show so ? (ii) Out of Cr_(3+) and Mn^(3+) which is a stronger oxidising agent and why? (iii) Why is zinc not regarded as a transition element ? (At. no. Zn=3)

(i) Name the element of 3d transition series which shows maximum number of oxidation states. Why does it show so ? (ii) Complete the following equation : MnO_(4)^(-) + 8H^(+) + 5e^(-) to .

Give reason: (i) Transition metals show variable oxidation states. (ii) Actinoids show wide range of oxidation states.

Give reason for the following : (i) Mn shows the highest oxidation state of +7 with oxygen but with fluorine, it shows the highest oxidation state of +4 (ii) Transition metals show variable oxidation states. (iii) Actinoids show irregularities in their electronic configurations.