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A gas mixture contains 1.20 g N2 and 0.77 g O2 in a 1.65-L container at 15 ∘C. Part A Calculate the mole fraction of N2. Express your answer using two significant figures. X1 X 1 = nothing Request Answer Part B Calculate the mole fraction of O2. Express your answer using two significant figures. X2 X 2 = nothing Request Answer Part C Calculate the partial pressure of N2. Express your answer using two significant figures. P1 P 1 = nothing atm Request Answer Part D Calculate the partial pressure of O2. Express your answer using two significant figures. P2 P 2 = nothing atm Request Answer Provide Feedback

User JesuLopez
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1 Answer

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Step-by-step explanation:

Moles of nitrogen gas =
n_1=(1.20 g)/(28 g/mol)=0.0428 mol

Moles of oxygen gas =
n_2=(0.77 g)/(32 g/mol)=0.0240 mol

Mole fraction of nitrogen gas=
\chi_1=(n_1)/(n_1+n_2)


\chi_1=(0.0428 mol)/(0.0428 mol+0.0240 mol)=0.6407\approx 0.64

Mole fraction of oxygen gas=
\chi_2=1-\chi_1=1-0.6407=0.3593\approx 0.36

Total umber of moles in container :

n =
n_1+n_2= 0.0428 mol + 0.0240 mol = 0.0668 mol

Volume of the container = V = 1.65 L

Temperature of the container = T = 15°C = 288.15 K

Total pressure in the container = P

Using an ideal gas equation:


PV=nRT


P=(0.0668 mol* 0.0821 atm L/mol k* 288.15 K)/(1.65 L)

P = 0.9577 atm

Partial pressure of nitrogen gas =
p^(o)_1

Partial pressure of nitrogen gas =
P^(o)_2

Partial pressure of nitrogen gas and oxygen gas can be calculated by using Dalton's law of partial pressure:


p^(o)_i=p_(total)* \chi_i


p^(o)_1=P* \chi_1=0.6135 atm\approx 0.61 atm


p^(o)_2=P* \chi_2=0.3441 atm\approx 0.34 atm

User Will Chu
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