Using Graham's Law
Graham's Law allows us to calculate how much faster one gas will diffuse than another. However, with a small change, we can make the equation even more useful. Remembering that rate = distance/time, we can substitute into the equation, yielding:
Graham's Law can now be used to find times or distances, as in the following problem:
If it takes helium 38.3 seconds to cross a 100.0 meter room, how long will it take oxygen to cross a 400.0 meter room?
Let's solve this problem.