Relationship between temperature and volume at constant pressure

Note how at -273oC the volume of a gas theoretically becomes zero. This is called the absolute zero and gives rise to a new temperature scale called the absolute temperature scale. This new temperature scale is given the symbol K and is called the Kelvin, after Lord Kelvin who first suggested it. At absolute zero the gas molecules have no kinetic energy
To convert from Celsius to Kelvin we simply add 273 to the Celsius value.
Celsius + 273 = Kelvin
Click to try some exercises in converting Celsius to Kelvin.
As seen in the animation above, at constant pressure, the volume of a fixed mass of gas is directly proportional to the absolute temperature . The formula on the right represents the relationship. This is known as Charle's Law after the famous French scientist, Jacques Charles.
In this expression K is a constant, V is volume in litres and T is temperature in degrees Kelvin.