# If there are a 10*mol quantity of CARBON ATOMS in a sample of propane, what is the molar quantity of this hydrocarbon?

There are clearly $\frac{10}{3}$ $m o l$ propane. Why?
Each formula unit of propane contains 3 carbon atoms, and 8 hydrogen atoms. Thus if there are $10.0$ $m o l$ carbon atoms in the propane sample, there are:
$\frac{10}{3}$ $m o l$ ${C}_{3} {H}_{8}$ and $\frac{80}{3}$ $m o l$ $H$ atoms.