Question

a compound is
○ a pure substance that cannot be broken down into simpler, stable substances.
○ a pure substance made of two or more types of atoms that are chemically bonded together.
○ the smallest unit of matter that maintains its chemical identity.
○ any substance, whether it is chemically bonded or not.

Explanation:

• Analyze each option:
• First option: Describes an element (cannot be broken down), not a compound.
• Second option: A compound is a pure substance with two or more types of atoms (elements) chemically bonded, which matches the definition.
• Third option: Describes an atom, not a compound.
• Fourth option: Too vague and incorrect, as compounds require chemical bonding of specific atom types.

Answer:

B. a pure substance made of two or more types of atoms that are chemically bonded together.