Prolonged boiling of a salt soluation (NaCl) results in a steady rise in the boiling point. Account for this effect. 

1 Answer

jerichorayel's profile pic

jerichorayel | College Teacher | (Level 2) Senior Educator

Posted on

Relating with the boiling point elevation, the addition of solute in the solution would increase the temperature of the boiling point. The expression:

`Delta T = K_b * m * i`


`m` = molality 

`k_b` = Ebullioscopic constant

`i ` = Van't Hoff factor

`Delta T` = (boiling point solution - boiling point pure solvent)

From the given expression, `Delta T` is directly proportional with the molality. As time passes by, the water molecules will evaporate thus increasing the molality of the solution. Increasing the molality will increase the temperature of the solution.