Gases

If the pressure of a gas remains constant, which temperature change would cause the volume of a gas to be reduced by half?

• 400 K to 200 K

• 200 K to 400 K

• 400^oC to 200^oC

• 200^oC to 400^oC

• more than one of these is a correct answer

What is the gas pressure in the manometer shown here.

Patm = 750 mm Hg and Δh = 30 mm

• 750 mm Hg

• 720 mm Hg

• 780 mm Hg

• 30 mm Hg

Consider two 1 L samples of gas:  One is He and the other is Ne. 

Both are at 1 atm and 25 ^oC.  Which statement is true?

• They have the same average kinetic energy

• They have the same density.

• They have the same average speed.

• They have the same mass.

At 0 °C a 22.4 L container holds 1.00 mole of oxygen and 2.00 moles of nitrogen. 

What is the total pressure inside the container?

• 1 atm

• 2 atm

• 3 atm

• 22.4 atm

N₂(g) + 2O₂(g) → 2 NO₂(g)

What volume of nitrogen is needed to fully react with 18.0 L of oxygen?

• 18.0 L

• 9.00 L

• 36. 36.0 L

• 4.50 L

Which gas law would best be used to solve this problem?

If 250 mL of a gas at 1 atm and 300K weighs 2 grams, what is the molar mass of the gas?

• Graham's Law

• Combined Law

• Ideal Law

• Dalton's Law

A mixture is 75% He and 25% Ne. If the total pressure is 400 torr, what is the partial pressure of the neon?

• 400 torr

• 100 torr

• 300 torr

• 200 torr

The graph shows 3 different gases at the same temperature. Which gas has the greatest mass?

• A

• B

• C

• there is no way to tell from this information

A gas occupies a volume 11.2 L at STP. How many moles of gas are present?

• 1 mole

• 0.5 mole

• 2 mole

• 11.2 mol

What gas law is best used to solve this problem?

A sample of Helium gas occupies 8 L at 1 atm and 20^oC. What is the new volume if the pressure changes to 2 atm and the temp rises to 80^oC?

• Combined Law

• Graham's Law

• Dalton's Law

• Ideal Law