at a constant temperature a gas is compressed from 4L to 1L. At 1L, the pressure of the gas is 98.2 kPa. What is the original pressure of this gas?

Answer: 24.6kpa

Explanation:

This is a classic case where Boyle's Law can be applied.

The equation for Boyle's Law is given as: P1V1 = P2V2

Where P1 = initial pressure

P2 = final pressure

V1 = initial volume

V2 = final volume

From the question, P1 = ?, P2 = 98.2kpa, V1 = 4L, V2 = 1L

P1V1 = P2V2

P1 x 4L = 98.2 kpa x 1L

Make P1 subject of formula we then have:

P1 = 98.2kpa X 1L / 4L

= 24.6kpa