At certain hill-station, pure water boils at 99.725ºC. If Kb for water is 0.513ºC kg mol–1, the boiling point of 0.69m solution of urea will be

0 0 99.725 ? b b T C T 0.69 b b M m T K m 0 0 0.69 0.513 0.69 0.513 99.725 100.079 b b b b T T T T C x x Note : Do not take 0 bT of water as 0 100 C as in the case at high altitude 0 bT for every solvent depend on the pressure of the surrounding. In this case 0 0 99.725 bT C