Unit 8 Pretest Gas Laws

Under which conditions do gases behave most ideally?

• low pressure and low temperature

• low pressure and high temperature

• high pressure and low temperature

• high pressure and high temperature

Which of these statements is true regarding the boiling point of water at the top of a mountain?

• The elevation of the mountain has no effect on the boiling point of water.

• The water will boil at a temperature less than 100°C.

• The water will boil at 100°C.

• The water will boil at a temperature greater than 100°C.

A 5.0 L sample of gas is heated from 15°C to 30°C. If the pressure remains constant, the volume would be expected to...

• decrease by half.

• double.

• decrease slightly.

• increase slightly.

A 100.0 L container is filled with 0.50 mol H2(g), 0.70 mol O2(g), and 1.80 mol SO2(g). If the total pressure inside the flask is 760 torr, what is the partial pressure of the H2(g)?

• 163 torr

• 326 torr

• 127 torr

• 653 torr

A 3.56 L balloon is inflated at standard pressure and temperature. If the temperature around the balloon is held constant but the pressure drops to 725 mmHg, what will the new volume of the balloon be?

• 3.73 L

• 1.96 L

• 0.53 L

• 1.53 L

If the gas confined in a balloon with a volume of 3.84 L container initially at 28.2°C were increased to 30.2°C the gas' new volume would be:

• 4.78 L

• 0.85 L

• 1.90 L

• 3.87 L

Pressure is-

• defined as the force per unit area.

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

• measured in Newtons.

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

A glass column is filled with mercury and inverted in a pool of mercury. The mercury column stabilizes at a height of 687 mm above the pool of mercury (Hg). What is the pressure of the atmosphere around the pool in atmosphere (atm)?

• 1 atm

• 6.87 atm

• 0.90 atm

• 91.60 atm

You fill a balloon with 7.7 moles of gas at 46°C at a pressure of 1.5 atm. What is the volume of the balloon?

• 228 L

• 19.52 L

• 0.05 L

• 134 L

Which gas would have a lower rate of effusion than O2?

• CO₂

• Cl₂

• N₂

• He