A gas mixture contains 0.70 moles of nitrogen gas, 0.20 moles of hydrogen gas, and 0.10 moles of methane (CH4). What is the partial pressure of nitrogen?

1 Answer
Sep 24, 2014

If the total pressure of the mixture is 1.00 atm, the partial pressure of nitrogen is 0.70 atm.

The partial pressure #P_"i"# of a gas #i# is equal to its mole fraction #x_i# times the total pressure #P_i# of the mixture.

#P_"i" =x_"i"P_"tot"# and #x_i = n_"i"/n_"tot"#.

#n_"tot" = n_"N₂" + n_"H₂" + n_"CH₄"# = (0.70 + 0.20 + 0.10) mol = 1.00 mol

#x_"N₂" = "0.70 mol"/"1.00 mol"# = 0.70

#P_"N₂" = x_"N₂"P_"tot"# = 0.70 × 1.00 atm = 0.70 atm