What happens to the pressure of a constant mass of gas at constant temperature when the volume is doubled?

Question

The pressure is doubled.

The pressure remains the same.

The pressure is reduced by 1/2.

The pressure is reduced by 1/4.

Answer 1

According to Boyle's Law, Pressure and Volume are inversely proportional to each other.

P ∝ 1/V

If the volume is doubled, then the pressure should decrease by 1/2 (answer choice c).

You can use the equation P1V1 = P2V2 and some basic numbers to figure out the solution.

P1 = 1 atm

V1 = 1 L

P2 = ?

V2 = 2 L

Rearrange the equation to solve for P2

P2 = P1V1 / V2 = (1 atm x 1 L) / 2 L = 1/2 atm

Pressure decreased from 1 atm to 1/2 atm. Hope that above was helpful!