Question

A complex of iron and cyanide ions is `100%`ionised ar `1`m (molal). If its elevation in b.p.is `2.08` then the complex is `(K_(b)=0.52^(@)mol^(-1)kg)`,
A. `K_(3)[Fe(CN)_(6)]`
B. `Fe(CN)_(2)`
C. `K_(4)[Fe(CN)_(6)]`
D. `Fe(CN)_(4)`

Answer 1

Correct Answer - A
`DeltaT_(b)=iK_(b)m`
so `i=(2.08)/(0.52xx1)=4`
so the compex is `K_(3)[Fe(CN)_(6)]`
`K_(3)[Fe(CN)_(6)]hArr3K^(+)+[Fe(CN)_(6)]^(3-)`