Increasing the **temperature** allows a gas to absorb **thermal energy** and convert into **kinetic energy**. Kinetic energy allows the gas to move and the speed at which it moves gives us the **root mean square speed**.

**Concept:** Understanding kinetic energy & Root Mean Square Speed

**Example:** A 1.56 x 10** ^{13}** pg gaseous particle travels at 6.21 . Determine its kinetic energy.

The kinetic energy (in J or kJ) of a gas molecule is directly proportional to its absolute temperature in Kelvins.

**Problem:** Calculate the molar mass, in g/mol, of a gaseous compound with an average root mean velocity of 652 m/s at a temperature of 30 degrees Celsius.

Remember that using the root mean square speed equation deals with molar mass in g/mol, so further conversion may sometimes be needed.

Effusion is the rate at which a gas escapes a container with an opening in it.

**Concept:** Understanding Graham's Law of Effusion

When comparing the **rate or speed of two gases** then we must use **Graham’s Law of Effusion**.

**Example:** Calculate the ratio of the effusion rates of helium and methane (CH_{4}).

The gas named first will represent gas 1 and the second gas will represent gas 2. Once that is established we simply use Graham’s Law of Effusion.

**Example:** Rank the following in order of increasing rate of effusion:

O_{2} AlF_{5} CO_{2} Xe