You have a 155-g sample of Al2O3. If there are 22.5 g of Al in the solution, what is the percent by mass of the solute? Use details to support your answer.

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).