Charles's Law

The pressure that a gas exerts on the walls of its container is determined by the momentum of the atoms and the molecules of the gas, which in turn is determined by temperature. As the temperature increases the atoms and molecules move faster, and so exert a greater pressure on the walls. If the walls are rigid, such that the volume of the container is held constant, the relationship between pressure P and temperature T is given by P = constant x T.

However, if the walls are flexible, as the temperature increases the volume increases to maintain even pressure. This is called Charles’s Law.

Charles law states that the volume of a given amount of dry ideal gas is directly propotional to the Kelvin Temperature, provided the amount of gas and the pressure remains fixed. i.e.

V=constant ( t + 273.15)
                Where t is the gas temperature on Celsius scale.

There are interesting points regarding the relationship between volume and temperature changes.

-273ºCT (ºC)

Since gases expand and contract at a constant rate, extrapolation of this behavior shows that the effective volume goes to zero around -273 ºC. One implication is that temperatures cannot be lower than -273 ºC.




T (K)         

-If -272 ºC were used as absolute zero,

Where K is degrees Kelvin, then volume expansion is directly proportional to temperature measured on the Kelvin, or absolute, temperature scale. That is,

or

=const. 
T

Join now!

or

=
T1 T2

Charles's law is a special case of the  equation andconcludes that the volume of any gas should extrapolate to zero at t = - 273.15 C. This law may be stated as following equation:

V=constant T                                         where T is the absolute temperature.

The aim of this investigation is to prove Charles’s law and through that to find a value for absolute zero. To prove this law, I shall carry out an experiment in which a volume of air is trapped inside a capillary tube at a constant pressure, this is attached ...

This is a preview of the whole essay