Question

If `9 L` of a gas at room temperature exerts a pressure of `12 kPa` on its container, what pressure will the gas exert if the container's volume changes to `4 L`?

Answer 1

`color(purple)("27 kpa"`

Explanation:

Let's identify our knowns and unknowns:

The first volume we have is `9 L`, the first pressure is `12kPa`, and the second volume is `4L`. Our only unknown is the second pressure.

We can ascertain the answer using Boyle's Law:

Rearrange the equation to solve for `P_2`

We do this by dividing both sides by `V_2` in order to get `P_2` by itself:
`P_2=(P_1xxV_1)/V_2`

Now all we have to do is plug in the given values:
`P_2=(12\kPa xx 9\ cancel"L")/(4\cancel"L")` = `27 kPa`