Question

At certain Hill-station pure water boils at `99.725^(@)C`. If `K_(b)` for water is `0.513^(@)C kg mol^(-1)`, the boiling point of `0.69m` solution of urea will be:
A. `100.079^(@)C`
B. `103^(@)C`
C. `100.359^(@)C`
D. unpredictable.

Answer 1

Correct Answer - A
`Delta T_(b) = K_(b) xx m =0.513 xx 0.69 = 0.354,`
`T_(b) = 99.725 + 0.354 = 100.079^(@)C.`