Like skim milk, whole milk is mostly water and contains casein, but whole milk also contains significant quantities of butterfat. Without the casein, the butterfat and water would separate into distinct layers, like the layers in vinaigrette salad dressing. As it is, the particles in whole milk are small enough that they pass right through the coffee filter. This is discussed more in a subsequent section , where a good extension based around milk is described. Coming up with familiar examples here was tricky.
Automotive antifreeze is a solution, about equal parts of ethylene glycol and water.
While water freezes at 32 o F, ethylene glycol doesn't freeze until 9 o F, and solutions of the two don't actually freeze until temperatures lower than either. Gasoline is a mixture of hundreds of different species, most of which are liquids at room temperature when pure. That gasoline is a solution rather than a physical mixture is very important, because any solid particles in gasoline will clog the fuel filter. Physical Mixtures Foam . Solutions Seltzer water in the bottle .