Question

A sample of helium gas occupies 1300 mL at 950 mmHg. For a gas sample at constant temperature, determine the volume of helium at 420 mmHg.

Answer 1

Answer – We are given, V1 = 1300 mL , P1 = 950 mm Hg

P2 = 420 mm Hg , V2 = ?

We know at constant temp, the volume of gas is inversely proportional to the pressure of gas. This is Boyle’s law and its formula as follow –

P1V1 = P2V2

So, V2 = P1V1 /P2

            = 1300 mL * 950 mm Hg / 420 mm Hg

            = 2940 mL

So, the volume of helium at 420 mmHg is 2940 mL