Science Review

The figure above represents three sealed 1.0 L vessels, each containing a different inert gas at 298 K. The pressure of Ar in the first vessel is 2.0 atm. The ratio of the numbers of Ar, Ne, and He atoms in the vessels is 2:1:6, respectively. After all the gases are combined in a previously evacuated 2.0 L vessel, what is the total pressure of the gases at 298 K?

• 3.0 atm

• 4.5 atm

• 9.0 atm

• 18 atm

When 4.0 L of He(g), 6.0 L of N₂(g), and 10. L of Ar(g), all at 0^oC and 1.0 atm, are pumped into an evacuated 8.0 L rigid container, the final pressure in the container at 0^oC is

• 0.5 atm

• 1.0 atm

• 2.5 atm

• 4.0 atm

A mixture of the gases neon and krypton is in a 2.00 Liter container. The partial pressure of the neon is 0.40 atm and the partial pressure of the krypton is 1.20 atm. What is the mole fraction of neon?

• 0.20

• 0.25

• 0.33

• 0.60

When 0.34 moles of He are mixed with 0.51 moles of Ar in a flask, the total pressure in the flask is found to be 5.0 atm. What is the partial pressure of Ar in this flask?

• 0.85 atm

• 1.5 atm

• 2.0 atm

• 3.0 atm

What is the pressure exerted by some nitrogen gas collected in a tube filled with water on a day when the room temperature is 18.0 °C and the room pressure is 750.0 mmHg? [The partial pressure of water at 18 °C is 15.5 mmHg.]

• 15.5 mmHg

• 750.0 mmHg

• 734.5 mmHg

• 765.5 mmHg

A mixture of gases at 810 kPa pressure contains:

3.0 moles of oxygen gas,

2.0 moles of helium gas, and

4.0 moles of carbon dioxide gas.

What is the partial pressure of helium gas, P_He.

• 405 kPa

• 810 kPa

• 81.0 kPa

• 180 kPa

A sealed flask contains 1 molecule of hydrogen for every 3 molecules of helium at 20 °C. If the total pressure is 400 kPa, the partial pressure of the hydrogen is…

• 100 kPa

• 200 kPa

• 300 kPa

• 400 kPa