12. Which of the following most accurately describes what the pH scale measures? the strength of a compound.
the strength of a base
the concentration of acids and bases.
the concentration of an acid

Wagons/motorized vehicles

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).