0.2 m aqueous solution of a weak acid (HX) is 20% dissociated. The boiling point of this solution is ( `K_(b)` for water `= 0.52 Km^(-1)`)

Options

A. `101.04^(@)C`
B. `100.104^(@)C`
C. `100.1248^(@)C`
D. `100.52^(@)C`

Answer

C

Explanation

`{:(" HX(aq)",rarr," H"^(+),+," X"^(-)),(m(1-0.20),,m(0.20),,m(0.20)):}`
Molal conc. of soln.
`=m(1-0.20)+0.20m +0.20m`
`=1.20m`
`DeltaT_(b)=K_(b) xx m`
`=0.52 xx 1.20(0.2)=0.1248`
Boiling point `=100.1248^(@)C`