Question

9. Molecules of compounds are made up of __________ .

• A. only one kind of atom
• B. only two atoms
• C. two or more kinds of atoms
• D. more than three atoms

Answer 1

The correct option is C

two or more kinds of atoms

Explanation:

• A compound is defined as a pure substance that is made up of two or more elements in a fixed ratio by mass.
• For example, Carbon dioxide $\left({\mathrm{CO}}_2\right)$ is a compound that is formed when one atom of carbon $\left(\mathrm{C}\right)$ combines with two atoms of oxygen $\left(\mathrm{O}\right)$.
• A molecule of a compound is formed when two or more different kinds of atoms are combined.

Hence, option (C) is the correct answer. Molecules of compounds are made up of two or more kinds of atoms.