Question

which choice is a compound?
carbon dioxide
air
carbon
oxygen

Explanation:

A compound is a substance formed when two or more elements are chemically bonded together. Carbon dioxide (\(CO_2\)) is composed of carbon and oxygen elements chemically combined. Air is a mixture of gases (like \(N_2\), \(O_2\), \(CO_2\) etc.). Carbon (\(C\)) and oxygen (\(O_2\)) are elements (pure substances made of only one type of atom).

Answer:

carbon dioxide