The compound with a chemical formula of C₃H₈ is propane. The subscripts actually represent the number of the individual atoms in 1 particle of the compound. Since there are the same number of atoms per mole of any substance, the subscript can also represent the moles. Through stoichiometric calculations, the solution is as follows:
Moles of Carbon = 11.2 moles H * 3 mol C/8 mol H = 4.2 moles