Question

which statement is true of pure substances?

o they can only contain one type of molecule.

o they can only contain one type of atom.

o they can contain different types of atoms and molecules.

o they may contain one type of atom or one type of molecule.

Explanation:

A pure substance can be an element (one type of atom) or a compound (one type of molecule). For example, oxygen gas (\(O_2\)) is a pure substance with one type of molecule, and pure gold (\(Au\)) is a pure substance with one type of atom. So a pure substance may contain one type of atom or one type of molecule.

Answer:

They may contain one type of atom or one type of molecule.