Question

what atom should be balanced last when balancing hydrocarbon combustion reactions?
a. the carbon atoms
b. the hydrogen atoms
c. any of the three
d. the oxygen atoms

Explanation:

In hydrocarbon combustion reactions, carbon and hydrogen are part of the hydrocarbon reactant. Oxygen comes from an external source like oxygen gas. It's easier to balance oxygen last as it is present in a separate reactant and adjusting its coefficient doesn't affect the balance of carbon and hydrogen.

Answer:

D. The oxygen atoms