# Gas Law Worksheet I - Answer Key

Go to the Gas Law WS I.

1. a) The gas molecules move faster because they have more kinetic energy. Because of the faster motion, more collisions occur causing the pressure to increase.
b) The molecules are moving slower so in order to keep the pressure constant (same number of collisions) the volume must decrease to give the molecules less space to move around in.
c) By adding more molecules, the number of collisions increases. The container must be cooled to slow down the molecules so that the number of collisions is reduced to the original level.
2. Volume is directly related to the moles of gas. By tripling the number of moles of gas, the volume must also triple in order to keep the pressure the same, i.e. the same number of collisions. Therefore the volume increases to 6.0 L.
3. The volume must increase in order to keep the collisions constant. The molecules are moving faster since they are heated so they need more space to keep the pressure constant.
1. The reading will be high since the tires are warm. This is not offset by the fact that you decreased in altitude, which would make the reading low (see next question).
2. You need to add air to the tires.