7.18, 7.19

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

Boyle's law states that:

• Equal amounts of gases occupy the same volume at constant temperature and pressure.

• The volume of a fixed amount of gas is inversely proportional to its pressure at constant temperature.

• The volume of a fixed amount of gas is directly proportional to its temperature in Kelvin at constant pressure.

• The total pressure of a mixture of gases is the simple sum of the partial pressure of all of the gaseous compounds.

• The rates of effusion of gases are inversely proportional to the square roots of their molar masses.

Charles's law states that:

• Equal amounts of gases occupy the same volume at constant temperature and pressure.

• The volume of a fixed amount of gas is inversely proportional to its pressure at constant temperature.

• The volume of a fixed amount of gas is directly proportional to its temperature in Kelvin at constant pressure.

• The total pressure of a mixture of gases is the simple sum of the partial pressure of all of the gaseous compounds.

• The rates of effusion of gases are inversely proportional to the square roots of their molar masses.

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.

• 312 K

• 278 K

• 20.4 K

• 295 K

• 552 K

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.

• 2.32 L

• 2.51 L

• 2.15 L

• 4.64 L

• 1.16 L

Body temperature is about 309 K. On a cold day, what volume of air at 276 K must a person with a lung capacity of 2.2L breathe in to fill the lungs?

• 2.46L

• 1.97

• 2.08

• 3.93

Which of the following would increase the (gas) pressure of a system?

• Increase the Temperature
• Pump in more gas
• Decrease the volume
• All of these

A gas sample has an initial volume of 55.2 mL, an initial temperature of 35.0^oC and an initial pressure of 735 mm Hg. The volume is decreased to 48.8 mL and the temperature is increased to 72.5^oC . What is the final pressure ?

• 933 mm Hg

• 186 mm Hg

• 1.72 x 10³ mmHg

• 84.0 g Kr

The combined gas law allows us to determine relationships between temperature, pressure and the volume of gases, including those used in a gas balloon. What is the final pressure if 155.0 mL of a gas at 22.0^oC and 374 mmHg is cooled to 0^oC and has a final volume of 102.0 mL

• 526 mm Hg

• 614 mmHg

• 73.4 mmHg

• 39.1 mmHg

This graph represents which gas law ?

• Grahams law

• Avogadros law

• Boyles Law

• Charles Law