What is the term for the process of intermingling or mixing gas molecules?

The term for the process of intermingling or mixing gas molecules is diffusion. This phenomenon occurs when gas molecules move from an area of higher concentration to an area of lower concentration, effectively mixing themselves in the process. Diffusion is driven by the random motion of the molecules, which leads to an even distribution over time, making it a fundamental concept in various scientific fields, including chemistry and physics.

In contrast, convection involves the movement of fluid (liquid or gas) due to differences in temperature, while filtration refers to the process of separating solids from liquids or gases using a filter. Dissociation describes the process of a compound breaking down into its constituent parts, which is different from the mixing of gas molecules. Therefore, diffusion is the most accurate term related to the mixing of gases as described in the question.