Question

A gas at a pressure of `"203 kPa"` occupies `"40.0 L"`. If the pressure is decreased to `"35.0 kPa"`, what is the new volume? Assume the temperature is held constant.

Answer 1

The final volume of helium gas will be `"232 L"`.

Explanation:

This is an example of Boyle's law, which states that the volume of a given amount of gas, held at a constant temperature, will vary inversely with its pressure. This means that when the pressure is increased, the volume will decrease and vice versa

The equation to use is `"P_1V_1=P_2V_2`, where `P` represents pressure, and `V` represents volume.

Known
`P_1="203 kPa"`
`V_1="40.0 L"`
`P_2="35.0 kPa"`

Unknown
`V_2`

Solution
Rearrange the equation to isolate `V_2`. Substitute the known values into the equation and solve.

`V_2=(P_1V_1)/(P_2)`

`V_2=(203cancel"kPa"xx40.0"L")/(35.0cancel"kPa")="232 L"`

The final volume of helium gas will be `"232 L"`.