Chapter 13, Problem 12STP

Interpretation Introduction

Interpretation:

The shape of pressure-volume graph is to determine when the temperature of gas is constant.

Concept introduction:

When temperature and amount of gas are constant, pressure of gas is inversely proportional to the volume of the gas. This law is known as Boyle's Law.

According to this law,

$\begin{array}{c}P\propto \frac{1}{V}\\ \therefore P=\frac{cons\tan t}{V}\end{array}$

Answer to Problem 12STP

E

Explanation of Solution

The change in volume on changing the pressure of the gas keeping the temperature fixed is studied by a law named as Boyle's Law. According to this law, Product of pressure and volume of a given mass of gas is constant at constant temperature.

$\begin{array}{c}P\propto \frac{1}{V}\\ Or\\ v\propto \frac{1}{P}\\ \therefore V=\frac{cons\tan t}{P}\end{array}$

As volume is inversely proportional to pressure so the slope of graph will be negative and its shape will be as shown in option E.

Conclusion

• Option A is wrong because according to it, pressure has no change on volume.
• Options B, C are wrong because slope of graphs is positive.
• Option D is wrong because according to it, volume firstly increases, reaches to a maximum value then decreases.

All these points are violated by Boyle's Law.