AP Chemistry Gas Laws

According to kinetic molecular theory, in which of the following gases will the root mean square speed of the molecules be the highest at 200ºC?

• SF₆

• H₂O

• HCl

• Cl₂

• None, the molecules of all gases have the same root mean square speed at any given temperature.

A sample of a gas (5.0 mol) at 1.0 atm is expanded at constant temperature from 10.0 L to 15.0 L. The final pressure is ___ atm.

• 1.5 atm

• 15 atm

• 0.67 atm

• 3.3 atm

• 7.5 atm

A sample of He gas (2.35 mol) occupies 57.9 L at 300.0 K and 1.00 atm. The volume of this sample is ___L at 423 K and 1.00 atm.

• 0.709 L

• 57.9 L

• 41.1 L

• 81.6 L

• 1.41 L

The density of N₂O at 1.52 atm and 45.2ºC is ____ g/L.

• 0.388 g/L

• 2.58 g/L

• 9.99 g/L

• 1.76 g/L

• 18.2 g/L

The volume of a sample of gas (2.49 g) is 752 mL at 1.98 atm and 62ºC. What is the gas?

• NO₂

• SO₃

• SO₂

• Ne

• NH₃

The pressure in a 12.2 L vessel that contains 2.34 g of carbon dioxide, 1.73 g of sulfur dioxide and 3.33 g of argon; all at 42ºC is ____ mmHg.

• 116 mmHg

• 395 mmHg

• 134 mmHg

• 263 mmHg

• 0.347 mmHg

Gases generally have

• low density

• high density

• closely packed particles

• no increase in volume when temperature is increased

• no decrease in volume when pressure is increased

Pressure is

• defined as the mass that an object exerts when at rest

• measured in Newtons

• defined as the number of moles of substance divided by the mass of the substance

• defined as the force per unit area

• measured in grams

A gas sample is held at constant pressure. The gas occupies 3.62 L of volume when the temperature is 21.6°C. Determine the temperature at which the volume of the gas is 3.42 L.

• 312K

• 278K

• 20.4K

• 295K

• 552K

A balloon has a volume of 2.32 liters at 24.0°C. The balloon is heated to 48.0°C. Calculate the new volume of the balloon.

• 2.32L

• 2.51L

• 2.15L

• 4.64L

• 1.16L