## Chemistry 9th Edition

The partial pressure of $H_2$ is 12.2 atm. The partial pressure of $He$ is 6.15 atm. The total pressure is 18.4 atm.
Partial Pressure of $H_2$ $1.00\text{ grams$H_2$}*\frac{1 \text{ mol$H_2$}}{2.01588\text{ grams$H_2$}}=0.496\text{ mol$H_2$}$ $P=\frac{nRT}{V}=\frac{0.496*0.08206*300}{1.00}=12.2\text{ atm}$ Partial Pressure of He $1.00\text{ grams$He$}*\frac{1 \text{ mol$He$}}{4.00260\text{ grams$He$}}=250\text{ mol$He$}$ $P=\frac{nRT}{V}=\frac{250*0.08206*300}{1.00}=6.15\text{ atm}$ Total pressure = 12.2 atm + 6.15 atm = 18.4 atm