Chapter 15, Problem 11CR

Interpretation Introduction

Interpretation:

The effect on a gas sample when it is collected by displacement of, or by bubbling through, water is to be stated and how this is taken into account when the pressure of the gas is calculated is also to be stated.

Concept Introduction:

The partial pressure of a gas can be defined as the total pressure exerted by all the gases in the container multiplied by their mole fraction.

Suppose two gases A and B are in a container and the partial pressure of A can be calculated as:

${\text{P}}_{\text{a}}=\frac{{\text{n}}_{\text{a}}}{{\text{n}}_{\text{a}}{\text{+n}}_{\text{b}}}\times \text{P}$

Where

• ${\text{P}}_{\text{a}}$ is the partial pressure of gas A.
• ${\text{n}}_{\text{a}}$ is the number of moles of A.
• ${\text{n}}_{\text{b}}$ is the number of moles of B.
• $\text{P}$ is the total pressure in the container.