### Charles’ Law

Charles’ law states that for a fixed mass of gas, the volume of the gas is directly proportional to the absolute temperature of the gas provided the pressure of the gas is kept constant.

$$\begin{array}{l}V\alpha T\\ V=kT\\ \frac{V}{T}=k\end{array}$$

$$\begin{array}{l}V\alpha T\\ V=kT\\ \frac{V}{T}=k\end{array}$$

#### Formula:

$$\frac{{V}_{1}}{{T}_{1}}=\frac{{V}_{2}}{{T}_{2}}$$#### Explanation

- When temperature increases, the average kinetic energy of the gas particles will increase.
- The air molecule move faster and collide with the wall of the container more vigorously at higher frequency.
- As a result, the space between the gas particles increases and the volume of the gas increases.

#### Graph

- In the graphs above, the first graph shows that V is directly proportional to the absolute temperature.
- The second graph shows that, if the temperature is in oC, the graph does not pass through the origin.
- The third and the forth graphs shows that V/T is always constant for all value of V and T.