The Variation With Temperature for a Fixed Mass of Gas of a Constant Volume.
We are trying to find out how the volume of a fixed amount of gas changes as its temperature is increased. .
Based on my previous work, I predict that the volume will increase when the temperature is increased. According to Charles' law pressure and volume are directly proportional ie. When the temperature is doubled the pressure is also doubled. This is because the particles have twice as much kinetic energy and consequently hit the walls of the container twice as often. This exerts an outward force on each unit of area, and hence this is pressure. .
Theory.
A graph that depicts volume and temperature is a straight line graph and so confirms that pressure increases uniformly with volume. The graphs do not pass through 0 Celcius, instead (if the line is retracted back), they intercept x (temperature) at -273 C. This is known as absolute zero, and is known as 0°C on the Kelvin temperature scale. .
Charles' Law.
The volume of a fixed mass of gas is directly proportional to its absolute temperature if the pressure is kept constant.
Pressure Law.
The pressure of a fixed mass of gas is directly proportional to its absolute temperature if the volume is kept constant. .
Boyle's Law.
When the pressure is increased on a fixed volume of gas kept at a constant temperature, the volume will decrease. The changes in pressure and volume are in inverse proportion. .
As previously mentioned, the kinetic theory offers an explanation to Boyle's law. The pressure that a gas exerts on a container is caused by molecules hitting the walls of the container. The pressure value depends on two things:.
1. How fast the particles are moving.
2. How often they hit the walls.
How often the particles hit the walls depend on how squashed up they are. When the volume is reduced, the particles become more squashed up and so they hit the walls of the container more often, and consequently the pressure goes up.
