Question

which statement correctly describes why a compound is a pure substance? a compound is not a pure substance because each of its molecules is made up of the atoms of two or more different elements. a compound is a pure substance because its molecule cannot be broken down into simpler particles by physical means. a compound is not a pure substance because it is not an element, and only elements are pure substances. a compound is a pure substance because it consists of two different elements, which are pure substances.

Explanation:

A pure - substance has a definite and constant composition. A compound is a pure substance because its molecules are chemically bonded and cannot be broken down into simpler particles by physical means. Physical means like cutting, melting, or boiling do not change the chemical nature of a compound's molecules.

Answer:

A compound is a pure substance because its molecule cannot be broken down into simpler particles by physical means.