Chemistry - Gases and pressure

Clue.
In order to keep the pressure constant we must keep the rate at which the molecules collide with the wall of container constant. When we increase the temperature we increase the average kinetic energy of the molecules. In other words we increase the average speed of the molecules. If the molecules are travelling faster think of how you will force them to hit the walls of the container less often.

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Pressure
	Look at the animation on the left. Notice how the rate of collisions changes as we alter the temperature, volume and number of particles. Increasing the temperature increases the average kinetic energy of the molecules. With a higher speed they reach the other side of the container in less time which increases the frequency of collisions. Increasing the number of particles will obviously increase the rate at which collisions occur as there is now a greater number of molecules capable of colliding with the walls of the container. Reducing the volume decreases the distance molecules have to travel before colliding with the wall.
Looking at the animation above, for a fixed amount of gas, think of how: - a decrease in pressure, without changing the temperature, is to be achieved. Solution - an increase in pressure, without changing the temperature, is to be achieved. Solution - the temperature of the gas can be increased without changing the pressure. Clue - the temperature of the gas can be decreased without changing the pressure.
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