Gas Laws and Root Square Mean

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