Graham's Law

According the Graham’s Law, the lower the molar mass of a gas, the quicker that gas will effuse and diffuse. Effusion takes place when a gas escapes out of a small container. Diffusion is best observed when gas molecules disperse throughout a given volume. In the image to the left, you see a release of aerosol spray. Does this represent diffusion or effusion? The gas coming out of the aerosol can is diffusing. The gas will spread out through the entire room where it is sprayed.