AP Chemistry Multiple Choice Practice Test

Question 1 of 3
63% Get this Question Right
A mixture of methane and helium is placed in a 2.0 L flask at 27 degrees Celsius. The partial pressure of CH4 is 0.72 atm and the partial pressure of helium is 0.22 atm. What is the mole fraction of methane?
0.77
3.5
0.50
0.29
0.23