Ideal Gas Mixtures and Partial Pressure

Question 1
Marks : +2 | -2
Pass Ratio : 100%
A gas mixture comprises of 20% CO2, 50% O2, and 30% N2 has the total pressure 100 Pa at temperature -73oC, if the temperature is increased to 27oC, what is the new partial pressure of N2?
15 Pa
30 Pa
45 Pa
60 Pa
Explanation:
P1/P2 = T1/T2, => 100/P2 = 200/300, => P2 = 150 Pa, => new partial pressure of N2 = 0.3*150 = 45 Pa.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
A gas mixture contains 30% CO2, 40% O2, 30% N2, if the partial pressure of CO2 is 6 Pa, what is the total pressure of gas mixture?
6 Pa
10 Pa
20 Pa
60 Pa
Explanation:
0.3*P = 6, => P = 20 Pa.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
The fraction of gas in a container is 0.1, if the total pressure of the container is 10 atm, what is the partial pressure of the gas?
1 atm
5 atm
10 atm
20 atm
Explanation:
Partial pressure of gas = 0.1*10 = 1 atm.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
A gas mixture contains 20% CO, 30% SO2, and 50% N2, if the partial pressure of N2 is 5 atm at 27oC, what is the molar volume of N2?
2.4 liter
3.7 liter
4.9 liter
5.6 liter
Explanation:
Total pressure of mixture = 5/0.5 = 10 atm, => Molar Volume of N2 = Total molar volume of mixture = 0.0821*300/10 = 2.4 liter.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
A container has gas mixture of 20% H2 and 80% N2 with total pressure P, now same amount of O2 is added to the mixture, what is the new partial pressure of N2?
0.2P
0.8P
P
1.6P
Explanation:
New partial pressure of N2 = Old partial pressure of N2 = 0.8P.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
A gas mixture has 30% O2, 40% H2, and 30% N2 with molar volume of N2 10 L/mole at temperature 27oC, what is the partial pressure of H2?
2.4 atm
3.6 atm
4.8 atm
6.4 atm
Explanation:
Molar volume of H2 = molar volume of N2 = 10 L/mole, PV = nRT, => P*10 = 0.0821*300, => P = 2.4 atm.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
A container has two gases at 27oC, one with molar volume 6 L/mole, another with molar volume 3 L/mole, what is the total pressure of the container?
6.9 atm
8.5 atm
12.3 atm
15.8 atm
Explanation:
p1V1 = n1RT1, => p1 = 0.0821*300/6 = 4.1 atm, p2 = 0.0821*300/3 = 8.2 atm, => P = 4.1 + 8.2 = 12.3 atm.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
The highest pressure gas of a mixture has partial pressure p, the partial pressure of other gases decreases by factor of 2n-1, the partial pressure of second gases decreases by a factor of 2, partial pressure of third gas increases by 4, and so on, if the total pressure of gas mixture is 31p/16, how many gases are present in the mixture?
3
5
10
15
Explanation:
Let n gases are present in the mixture, => p + p/2 + p/4 + – – – + p/2n-1 = 7p/8, => p(1 – 1/2n)/(1 – ½) = 31p/16, => n = 5.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
The fraction of gas in a container is 0.5, if the total volume of the container is 6 liter, what is the volume of the gas?
2 liter
3 liter
5 liter
6 liter
Explanation:
Volume of gas = Volume of container = 6 liter.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
A container has gas mixture of 40% CO2 and 60% H2 with total pressure 10 Pa, if now O2 is added to it isothermally so that the final composition of the mixture becomes 20% CO2, 30% H2, and 50% O2, what is the partial pressure of O2 in the new composition?
5 Pa
10 Pa
20 Pa
35 Pa
Explanation:
Partial pressure of H2 = 0.6*10 = 6 Pa, => Partial pressure of O2 = 0.5*6/0.3 = 10 Pa.