Question

Assertion : Potassium ferrocyanide is diamagnetic whereas potassium ferricyanide is paramagnetic. 

Reason : Crystal field splitting in ferrocyanide ion is greater than that of ferricyanide ion.

(a) Both A and R are true and R is the correct explanation of A

(b) Both A and R are true but R is not correct explanation of A

(c) A is true but R is false

(d) A and R are false

Answer 1

The correct option is (c) A is true but R is false.

Explanation:

Ferrocyanide ion

In ferrocyanide ion, the oxidation state of Fe is +2 however in ferricyanide ion, the oxidation number of Fe is +3. 

Generally, the higher the oxidation state of the metal, the greater the crystal field splitting. It means crystal field splitting in ferrocyanide ion is lower than that of ferricyanide ion.