1. 8.00 g of methane (CH4), 18.0 g of ethane (C2H6), and an unknown amount of propane (C3H8), were added to the same 10.0-L container. The total pressure in the container is 4.90 atm. Temperature is 23.0 ∘C. Calculate the partial pressure of each gas in the container. Express the pressure value in atmospheres.

2. A mixture of O2 gas and N2 gas contains 36.8 % nitrogen by mass. What is the partial pressure of oxygen in the mixture if the total pressure is 725 mmHg ?
Express you answer numerically in millimeters of mercury.