According to the Boyle's law, given a constant temperature, the pressure and volume of an ideal gas are inversely related. In other words:

P `alpha` 1/V

or, PV = constant

where, P is the pressure of the gas and V is its volume. This means that as long as the temperature stays constant, an increase in either the pressure or the volume will decrease the other quantity. Similarly, a decrease in one of them will cause the other property to rise.

Here, the original pressure is 760 mm Hg and the volume is increased by 20%.

that is , P1 = 760 mm, V2 = 120% of V1 = 1.2 V1

Using the Boyle's law: P1V1 = P2V2

or, P2 = P1V1/V2 = 760 x V1 / (1.2 V1) = 760/1.2 = **633.3 mm Hg**.

Thus, an increase of 20% in volume caused 20% reduction in the pressure of the air, at constant temperature.

Hope this helps.

## We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

- 30,000+ book summaries
- 20% study tools discount
- Ad-free content
- PDF downloads
- 300,000+ answers
- 5-star customer support

Already a member? Log in here.

Are you a teacher? Sign up now