Pressure is the force exerted by a substance per unit area on another substance. Gas pressure is the defined as the exertion of the walls of its container due to the collision of the gas particles with the sides of the container.
Therefore, any time the number of collisions with the sides of the container increases, so will the gas pressure.
The kinetic molecular theory states that all substances are constantly in motion- including gases. However, the speed (kinetic energy) of the gas molecules increases as temperature increases. Therefore, gas pressure can be increased by increasing the temperature of the gas molecules within the container. This is why a 2 liter of pop may explode in your car on a hot summer day!
We can also increase gas pressure by adding more gas particles within the container. This would result in more collisions with the sides of the container. Similarly, gas pressure can be increased by decreasing the volume of the container.
1. Gas pressure is due to the collisions of gas particles with their container.
2. Gas pressure can be increased by increasing the number of collisions with the container. Specifically by a) increasing the number of particles in the container, b) increasing the temperature, and c) decreasing the size of the container.