How Is Diffusion Used in Real Life?


Hi, I'm Sean Tvelia, and we're here at Suffolk County Community College to talk about how diffusion is used in real life but first let's talk about what diffusion is. Diffusion is simply the mixing of two materials based on kinetic energy of the molecules or atoms. So for example, if we look at this very simple concept of a jar or some vessel holding some molecules, all of the molecules because they have kinetic energy are in constant motion throughout that vessel as long as there's a lid on the vessel the molecules or atoms stay within the vessel, but as soon as I remove the lid, the kinetic energy, that is the energy of motion, allows these molecules to slowly leave the vessel. At the same time, it allows other molecules outside the vessel such as air molecules to enter the vessel. Over time, as the molecules continue to move slowly more and more of the molecules will exit the vessel and more of the air molecules will enter the vessel. So over time we will get even distribution of molecules or atoms within the vessel. We can see diffusion in real life in a number of ways. First, by steeping some tea by just leaving the teabag within the mug, slowly the tannins and the oils leave the tea and diffuse throughout the entire mug, or by dropping some green dye in water. If we just let the water sit, the green dye will slowly diffuse and fill up the entire vessel, or also through air diffusers that we use in our homes. By simply turning the dial, we open up the vessel and we allow molecules to slowly enter the air and over time the scent will diffuse throughout an entire room.

Professor Sean Tvelia is an Associate Professor of Geology at Suffolk County Community College.