Question

which best describes a compound such as sodium chloride?
a pure substance that can be separated into different elements by physical means
a mixture of two common substances that can be separated by chemical means
a mixture of two common elements that can be separated by physical means
a pure substance that can be separated into different elements by chemical means

Explanation:

Sodium chloride (NaCl) is a compound. Compounds are pure substances composed of two or more different elements chemically combined. These elements in a compound can only be separated by chemical means, not physical means. Mixtures are combinations of substances that can be separated by physical means.

Answer:

a pure substance that can be separated into different elements by chemical means