24. Compounds may be described by which of the following sentences? A. Pure substances that contain two or more elements. B. Materials that are composed of particles called molecules. C. Materials...

A. Pure substances that contain two or more elements.

B. Materials that are composed of particles called molecules.

C. Materials composed of more than one part, and the parts may be present in any proportion.

D. Substances that appear on the right hand side of the periodic table.