Question

If 1 g of solute (molar mass = $50gmol^{- 1}$) is dissolved in 50 g of solvent and the elevation in boiling point is 1 K. the molar boiling constant of the solvent is

• A. 2
• B. 3
• C. $2.5$
• D. 5

Answer 1

Answer: (C)

$2.5$

Answer 2

$\Delta T_{b} = K_{b} \times m$

Or $K_{b} = \frac{\Delta T_{b}}{m} = \frac{1}{\frac{1}{50} \times \frac{1000}{50}} = \frac{5}{2} = 2.5$