Which of the following is true about mixtures and compounds?

The substances in a mixture can be separated using physical methods such as filtration, freezing, and distillation. There is little or no energy change when a mixture forms. Mixtures have variable compositions, while compounds have a fixed, definite formula.

Compounds Facts. A chemical compound, made up of two or more different chemical elements, is a pure substance that can be put through various chemical reactions in order to separate its components. They have unique chemical structures based upon their parts, and their atoms are held together by chemical bonds.