Calculate the number of unpaired electrons in following gaseous ions: Mn3+, Cr3+, V3+ and Ti3+, which one of these is the most stable in aqueous solution?
Give example and suggest reasons for the following features of the transition metal chemistry:
The lowest oxide of transition metal is basic, the highest is amphoteric/acidic.
Give example and suggest reasons for the following features of the transition metal chemistry:
A transition metal exhibits highest oxidation state in oxides and fluroides.
Give example and suggest reasons for the following features of the transition metal chemistry:
The highest oxidation state is exhibited in oxoanions of a metal.
Indicate the steps in the preparation of K2Cr2O7 from chromite ore.
The preparation of potassium dichromate from chromite involves the following main steps:
(i) The chromate ore is finely ground and heated strongly with molten alkali in the presence of air.
(ii) The solution of sodium chromate is filtered and acidified with dilute sulphuric acid so that sodium dichromate is obtained.
(iii) A calculated quantity of potassium chloride is added to a hot concentrated solution of sodium dichromate. Potassium dichromate is less soluble therefore it crystallizes out first.