# How many moles of hydrogen atoms in one mole of methane, CH_4?

Well $4 \cdot \text{moles}$ of hydrogen atoms.......
One mole of methane specifies ${N}_{A}$, $\text{Avogadro's number}$ of methane molecules, i.e. $6.022 \times {10}^{23}$ individual $C {H}_{4}$ molecules. And thus it contains $4 \times 6.022 \times {10}^{23}$ $\text{hydrogen atoms}$.
I would have used precisely the same procedure if I were asked the number of $\text{hydrogen atoms}$ in $\text{4 dozen methane molecules}$; i.e. there are $4 \times 12 = 48$, $\text{four dozen}$, $\text{hydrogen atoms.....}$ The mole is simply a collective number like a $\text{dozen}$ or a $\text{gross}$.....admittedly, it is a much larger quantity.
The $\text{mole}$, however, has a special property: ${N}_{A}$ ""^12C atoms have a mass of $12.0 \cdot g$ precisely, and thus we use it as a means to equate the number of atoms, which we can estimate but not individually count, with a given mass of stuff.