Question

Do gases diffuse uniformly through a container to form homogeneous mixtures?

Answer 1

Yes they do.

Explanation:

If different gases are let into a container, either by differnt inlets, or in different order, they will swiftly diffuse to even out. This means that in every (tiny) bit of space in the container the same ratio of gases are present, molecule for molecule.
we call this a homogeneous mixture.

Note:
Gas mixtures are always homogeneous (unless they react of course).
Liquids that mix well are also homogeneous (like ethanol and water).