Which chemical formula represents propane?

Propane is an alkane with three carbon atoms and is represented by the chemical formula C3H8. In this formula, there are three carbon (C) atoms and eight hydrogen (H) atoms. This structure adheres to the general formula for alkanes, which is CnH2n+2. When n equals 3 (for propane), the equation yields C3H8, confirming its representation as propane.

In contrast to the other formulas provided, C2H6 corresponds to ethane (which has two carbon atoms), C4H10 corresponds to butane (with four carbon atoms), and C5H12 corresponds to pentane (which has five carbon atoms). Each of these has a different number of carbon and hydrogen atoms and represents distinct alkane compounds. Therefore, C3H8 is indeed the correct representation for propane.