Graham's Law states that the rate of effusion of a gas is inversely proportional to the square root of its molar mass.
Effusion involves a gas escaping a container through an opening.
Concept #1: 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 #1: Calculate the ratio of the effusion rates of helium and methane (CH4).
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 #2: Rank the following in order of increasing rate of effusion:
O2 AlF5 CO2 Xe