Applying Avogadro’s Law

20 g of H_{2} are put in a container and kept at STP. What is the volume of the hydrogen gas?
H_{2} = gas

STP = Standard temperature and pressure. This is very important for gases because PV = nRT
g-> moles because moles are useful

(1)   \begin{equation*}H_{2} = (1.01\frac{g}{mol}) * 2 = 2.02 \frac{g}{mol}\end{equation*}

(2)   \begin{equation*}\frac{20g}{1} \frac{1mol}{2.02g} = 2.02 \frac{g}{mol}\end{equation*}

Avogadro’s Law states that at STP 1 mol of gas takes up 22.4L. This is useful for mols to volume conversion.

(3)   \begin{equation*}\frac{9.9mol}{1} \frac{22.4 L}{1 mol} = 221.76 L\end{equation*}

So our container must hold hydrogen volume of \boxed{221.76}