Which two reactants are required for the combustion of a hydrocarbon?

• A. A hydrocarbon and N_2
• B. A hydrocarbon and CO_2
• C. A hydrocarbon and H_2O
• D. A hydrocarbon and O_2

Answer: (D)

Verified step by step guidance

1. Understand that combustion is a chemical reaction where a substance reacts with oxygen to produce energy, usually in the form of heat and light.
2. Recognize that hydrocarbons are compounds made of hydrogen and carbon atoms, and when they combust, they react with oxygen (O_2) from the air.
3. Recall the general combustion reaction for a hydrocarbon: \(\text{Hydrocarbon} + O_2 \rightarrow CO_2 + H_2O\) (carbon dioxide and water are typical products).
4. Note that nitrogen (N_2), carbon dioxide (CO_2), and water (H_2O) are not reactants in the combustion process; instead, oxygen (O_2) is the essential reactant that supports combustion.
5. Conclude that the two reactants required for the combustion of a hydrocarbon are a hydrocarbon and oxygen (O_2).