Chapter 14, Problem 92A

Interpretation Introduction

Interpretation:

The final pressure at given solubility is to be calculated.

Concept introduction:

Solubility: Solubility can be expressed as maximum amount of solute that can dissolve in a known amount of solvent at a given temperature and pressure.

Henry’s Law: In liquid, the solubility of a gas is directly proportional to its pressure above the liquid at given temperature.

Answer to Problem 92A

The pressure of the gas is 185kPa.

Explanation of Solution

Given information:

$S_1=1.8\mathrm{gm}/litre$

$P_1=37.0\mathrm{kPa}$

$S_2=9.0gm/litre$

The expression of Henry’s Law is $\frac{S_1}{P_1}=\frac{S_2}{P_2}$

The solubility of a gas is S₁ at P₁ pressure and S₂ at pressure P₂.

$\begin{array}{c}\frac{S_1}{P_1}=\frac{S_2}{P_2}\\ P_2=\frac{S_2\times P_1}{S_1}\\ {\mathrm{P}}_2=\frac{9.0gm/litre\times 37.0kPa}{1.8gm/litre}\\ =185kPa\end{array}$

So, the pressure of the gas is $185\mathrm{kPa}$.