Why do you think Vera and Domingo ended up with three substances after the chemical reaction while Lee only ended up with two? Pls actually answer it don’t say something

It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).

The second and last option are the answers