The elevation in boiling point of a solution of `13.44 g` of `CuCl_(2)` in `1 kg` of water using the following information will be (molecular weight of `CuCl_(2)` is 134.4 and `K_(b)=0.52 K m^(-1))`

Options

A. 0.16
B. 0.05
C. 0.1
D. 0.2

Answer

A

Explanation

`CuCl_2` is an electrolyte which ionise in solution as follows:


Thus, number of particles after ionization `=1-alpha +alpha+2alpha=1+alpha`
`therefore " Van't Hoff factor " (i) = ("number of praticles after ionisation")/("number of particles before ionisation") or (i) =(1+2alpha)/1 ("on" 100% "ionisation" alpha=1)`
`=(1+2xx1)/1=3`
The elevation in boiling point (when collogative property is abnormal)
`DeltaT_b =ixxK_b xxm`
m is the Molality of solution

Molality of `CuCl_2` solution = `(("Weight of"" " CuCl_2 " ""in gram")/("Mol.weight of" " "CuCl_2))/("Weight of water (Solvent) in kg ")=((13.44)/(134.4))/1=0.1m`
Thus `DeltaT_b=3xx0.52xx0.1 =0.156=0.16^@C`