More collisions mean more force, so the pressure will<span> increase. When the volume </span>decreases<span>, the </span>pressure<span> increases. This shows that the </span>pressure of a gas<span> is inversely proportional to its volume. ... It means that for a </span>gas<span> at a constant temperature, </span>pressure<span> × volume is also constant</span>
The combined gas law states that the pressure of a gas is inversely related to the volume and directly related to the temperature. If temperature is held constant, the equation is reduced to Boyle’s law. Therefore, if you decrease the pressure of a fixed amount of gas, it’s volume will increase.