The volume of a fixed mass of gas is 10cm³ when its pressure is 400cmHg. Determine the volume of the gas when its pressure is 200cmHg.

A. 30cm³
B. 40cm³
C. 50cm³
D. 20cm³

Correct Answer:

Option D – 20cm³

Explanation

Using boyle’s law

P1V1 = P2V2

V2 = P1V1/200 = 400×10/200

= 20cm³