I think I’m going to have to side with the Mrs. on this one - solution. If I understand my chemistry correctly, a suspension is made of two or more substances that, when combined, make up a new substance with its own, unique identity, whereas a solution is also made up of two more substances but is still identified primarily in terms of one of the substances. So, since you mix chocolate syrup in your milk to create chocolate milk, it is still identified in terms of milk, one of its primary components. As such, I think it probably settles into the category of solution.

I don’t want to correct Jim too strenuously, because I could be wrong, but I think he’s mistaken about the definition of a suspension. I was under the impression that in a suspension, the two substances remain separate but one is suspended in the other — like quicksand.

As for the question of chocolate milk, I’m having a hard time deciding, since the chocolate milk mix itself is made up of several ingredients, including cocoa (which could conceivably be a suspension) and sugar (which WILL dissolve in milk, making THAT part of chocolate milk a solution).

Mmm, yeah, I was more describing the outcome of the mix rather than the chemical interaction to create the mix. It was the easiest way, at least in my own mind, to describe the difference.

I gave a call to a scientist I know. She wasn’t sure herself - she’s not a chemist. But a chemist in her lab said that chocolate milk is neither. It is a colloid. Neither a suspension or solution, but a substance sort of in between.

Brian is very close in his description of the various components of the chocolate syrup joining with the milk in different ways.

I say solution.

Milk has emusifiers in it that help fats become soluable. Chocaolate, or at least coca, is/has oil/fat.

Another reason why its better to drink milk after you have hot pepers as the “hot” in the peppers is an oil too, and can be emulsified and removed, unlike with water.

So say i without googling

Back to the trenches.

The scientist is correct. Milk is a colloid.

The milk is a colloid and a solution when the galactose is considered as well as the various electorlytes. The proteins are what form the colloid and the fat droplets if it is homogenized.

But what about the chocolate syrup? It is a combination of solution, colloid and suspension, primarily suspension. The latter is easily demonstrated by adding chocolate to milk, stirring, and letting it sit. Eventually there will be sediment on the bottom of the vessel. Chocolate syrup has sugars and sometimes some salt in it, both of which are in solution. A good portion of the syrup would be considered colloid because it never settles out. It is too small to be effected by gravity, which is a good operational definition of colloid.