(a) Give preparation of potassium permanganate `(KMnO_4)`. (b) What is lanthanoid contraction, give its cause. (c ) Transition metals show catalytic properties. Explain.

(a) What is the cause of lanthanoid contraction? Discuss. (b) What is Misch metal?

(i) What are interstitial compounds ? (ii) Transition metals show good catalytic property. Give any two reasons.

(a) What is Lanthanoid contraction? Give the cause of lanthanoid contraction. (b) Why do transition metals form many coloured ions?

How will you obtain pure potassiu permanganate (KMnO_(4)) crystals from its ore pyrolusite? Give the steps involved in the reactions. .

(a) What is lanthanoid contraction? What is the cause of lanthanoid contraction? (b) Explain whether Cu^(2+) is paramagnetic or diamagnetic.

What is lanthanoid contraction? (b) Write any one use of lathanoid (c) \(La(OH)_{2}\) is more basic than \(Lu(OH)_{3}\) .Explain.

(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.