Chapter 14.4, Problem 38SP

Interpretation Introduction

Interpretation: To determine the total pressure of the mixture of gas.

Concept Introduction: A gas law known as Dalton's law of partial pressures asserts that the summation of the partial pressures exerted across all of the gases in a mixture exceeds the overall pressure that even the mixture of gases produces.

Answer to Problem 38SP

The total pressure will be $\text{90}\text{.4 kPa}$

Explanation of Solution

The given data:

Total pressure =?

  ${\text{Po}}_{\text{2}}$ = 20 kPa

  ${\text{P}}_{{\text{N}}_{\text{2}}}$ = 43.7 kPa

  ${\text{P}}_{\text{He}}$ = 26.7 kPa

According to Dalton’s law:

  ${\text{P}}_{\text{total}}{\text{=P}}_{{\text{O}}_{\text{2}}}{\text{+P}}_{{\text{N}}_{\text{2}}}{\text{+P}}_{\text{He}}\mathrm{.....}\text{(i)}$

Put the given data in the above equation.

  $\begin{array}{c}{\text{P}}_{\text{total}}{\text{=P}}_{{\text{O}}_{\text{2}}}{\text{+P}}_{{\text{N}}_{\text{2}}}{\text{+P}}_{\text{He}}\\ \text{=20 kPa+43}\text{.7 kPa+26}\text{.7 kPa}\\ =\text{90}\text{.4 kPa}\end{array}$

Therefore, the total pressure will be $\text{90}\text{.4 kPa}$ .