Question:

Boiling point of benzene is $353.23\, K$. When $1.8\, g$ of non-volatile solute is dissolved in $90\, g$ of benzene. Then boiling point is raised to $354.11\, K$. Given $K_b$ (benzene) = $2.53 \, kg\, mol^{-1}$. The molecular mass of non-volatile substance is

Updated On: Jun 23, 2023
  • $58 \,g\, mol^{-1}$
  • $120 \,g\, mol^{-1}$
  • $116 \,g\, mol^{-1}$
  • $60 \,g\, mol^{-1}$
Hide Solution
collegedunia
Verified By Collegedunia

The Correct Option is A

Solution and Explanation

$T_{b}^{\circ}=353.23 K,\, W_{B}=1.8\, g,$ $W_{A}=90\, g,\, T_{b}=354.11\, K,$ $K_{b}=2.53\, kg\, mol^{ -1}$ $\Delta T_{b}=T_{b}-T_{b}^{\circ}=354.11-353.23=0.88\, K$ $M_{B}=\frac{W_{B}\times K_{b}\times1000}{\Delta T_{b}\times W_{A}}=\frac{1.8\times2.53\times1000}{0.88\times90}$ $=57.5\approx 58\, g\, mol^{ -1}$
Was this answer helpful?
0
0

Questions Asked in AIIMS exam

View More Questions

Concepts Used:

Solutions

A solution is a homogeneous mixture of two or more components in which the particle size is smaller than 1 nm.

For example, salt and sugar is a good illustration of a solution. A solution can be categorized into several components.

Types of Solutions:

The solutions can be classified into three types:

  • Solid Solutions - In these solutions, the solvent is in a Solid-state.
  • Liquid Solutions- In these solutions, the solvent is in a Liquid state.
  • Gaseous Solutions - In these solutions, the solvent is in a Gaseous state.

On the basis of the amount of solute dissolved in a solvent, solutions are divided into the following types:

  1. Unsaturated Solution- A solution in which more solute can be dissolved without raising the temperature of the solution is known as an unsaturated solution.
  2. Saturated Solution- A solution in which no solute can be dissolved after reaching a certain amount of temperature is known as an unsaturated saturated solution.
  3. Supersaturated Solution- A solution that contains more solute than the maximum amount at a certain temperature is known as a supersaturated solution.