Chapter 5, Problem 73QAP

Interpretation Introduction

Interpretation:

The density and molar mass of an unknown gas are required to be determined.

Concept introduction:

Graham’s law may be formulated as:

$\text{rate }\alpha \frac{1}{\sqrt{\text{M}}}$

where M denotes the molar volume of the gas.

That means the rate of effusion of a gas and the square root of the mass of the particles of the gas is inversely proportional.

Under the same conditions of temperature and pressure, the molar volume of all gases is the same and hence, the Graham’s law may be written as:

$\text{rate }\alpha \frac{1}{\sqrt{\text{d}}}$

where d denotes the density of the gas.

The density of a gas is directly proportional to the molar mass of the gas (since molar volume is constant for all the gases).