Amixture is what you get when you combine two substances in such a way that no chemical reaction occurs between the components. a solution is a mixture that looks exactly the same everywhere. which of these mixtures is not a solution?

B) A chocolate chip cookie

Explanation:

The options you were given are:

A) A glass of apple juice;

B) A chocolate chip cookie;

C) A mixture of salt and water;

D) A mixture of sugar and water.

A solution is an even (homogeneous) mixture of substances, meaning that the individual components cannot be made out. Apple juice is an even, clear liquid, and so are mixtures of water and salt or sugar, as both salt and sugar are water-soluble. Out of the listed mixtures, a chocolate chip cookie is the only one that is not a solution - different components are visible to the human eye as they are not evenly distributed throughout the sample (unlike sugar and salt in water, which are not visible despite existing on the molecular level). Based on that, we can easily conclude that a chocolate chip cookie is a heterogeneous mixture.