Unit 2 Gases

What is the volume of 0.881 mole of a gas at standard temperature and pressure?

• 0.0401 L
• 19.7 L
• 22.4 L
• 39.4 L

The total pressure of a gas mixture is 1.05 atm. The mixture contains 55% carbon dioxide, 31% nitrogen, and 14% hydrogen. What is the partial pressure of the carbon dioxide in the mixture?

• 0.58 atm
• 0.47 atm
• 0.33 atm
• 0.15 atm

A tank contains 6.0 moles of a mixture of hydrogen gas, H2, and oxygen gas, O2. The total pressure exerted by the gas mixture on the tank is 500 kPa. The partial pressure of hydrogen is 150 kPa. How many moles of each gas are present in the mixture?

• 1.8 moles of H2 and 4.2 moles of O2
• 2.6 moles of H2 and 3.4 moles of O2
• 1.4 moles of H2 and 4.6 moles of O2
• 1.5 moles of H2 and 3.5 moles of O2

Tags

NGSS.HS-PS1-7

A sample of helium gas is stored in a tank at 18 atm and 20°C. How do these conditions compare to the conditions of a gas at STP?

• lower pressure and lower temperature than STP
• higher pressure and lower temperature than STP
• lower pressure and higher temperature than STP
• higher pressure and higher temperature than STP

Which statement describes the change in pressure of the gas inside an automobile emergency air bag as it inflates?

• There is an increase in pressure as the number of gas molecules increases.
• There is a decrease in pressure as the number of gas molecules increases.
• There is an increase in pressure as the gas molecules diffuse outside the bag.
• There is a decrease in pressure as the gas molecules diffuse inside the bag.

A container is divided in half, and each side contains a different type of gas. Gas 1 has a temperature of T1 and a pressure of P1. Gas 2 has a temperature of T2 and a pressure of P2. Gas 2 is hotter and under more pressure than Gas 1. How will the system change when the division is removed?

• The gases will mix uniformly with a final temperature of T2 and a pressure of P2.
• The gases will mix uniformly with a final temperature between T1 and T2 and a pressure of P2.
• The gases will mix uniformly with a final temperature of T2 and a pressure between P1 and P2.
• The gases will mix uniformly with a final temperature between T1 and T2 and a pressure between P1 and P2.

Tags

NGSS.HS-PS3-4

A sample of carbon dioxide has a pressure of 1.2 atm, a volume of 50.0 L, and a temperature of 650K. How many moles of carbon dioxide are included in the sample?

• 1.1 mol
• 0.9 mol
• 0.1 mol
• 2.6 mol

The normal pressure for a car tire is 220 kPa. The actual pressure reading for a tire is 262 kPa. Which of the following best explains why the actual pressure is greater than normal?

• An increase in molecules of gas produces fewer collisions against the inner tire surface.
• More collisions occur between the inner surface of the tire as gas molecule numbers increase.
• Random motion of gas molecules increases due to a decrease in the number of gas molecules.
• A change in the number of gas molecules in the tire causes the random motion to be unstable. less

When the temperature of a gas increases from 100K to 200K, what happens to the average kinetic energy of the molecules?

• The kinetic energy decreases by a factor of 2.
• The kinetic energy increases by a factor of 2.
• The kinetic energy decreases by a factor of 100.
• The kinetic energy increases by a factor of 100.

Tags

NGSS.HS-PS3-2

A sample of 0.02 mol of oxygen has a temperature of 399K and a volume of 5.00 L. What is its pressure?

• 0.13 atm
• 0.66 atm
• 3.28 atm
• 19.5 atm