Question 1

A paint thinner can is shown before and after a vacuum is applied. When the vacuum is on, the can collapses. Which gas law best explains why the can collapses when the pressure inside is much less than the pressure outside?

Accepted Answer

Boyle's Law: $$P_1$$ $$V_1$$ = $$P_2$$ $$V_2$$

Question 2

A gas sample is trapped in a J-tube at 20.0 mL and 780 torr. If the pressure is increased to 1560 torr, what will the new volume be, assuming temperature and amount of gas remain constant?

Accepted Answer

$$10.0\ 	ext{mL}$$

Question 3

Which of the following statements about gases is NOT correct according to the kinetic-molecular theory?

Accepted Answer

Gas particles lose energy during collisions due to friction.

Question 4

A helium-filled balloon has a volume of 15.8 L at 0.980 atm and 22°C. What will its volume be at 0°C and 0.700 atm? (Assume the amount of gas is constant.)

Accepted Answer

$$21.8\ 	ext{L}$$

Question 5

Which of the following best describes why atmospheric pressure decreases with altitude?

Accepted Answer

There is less mass of air above you as you go higher.

Question 6

A biologist prepares a gas mixture with 4.0 mole % $$^{18}O$_2 at a $$total pressure of 0.75 atm. What is the partial pressure of $$^{18}O$_2$$?

Accepted Answer

$$0.03\ 	ext{atm}$$

Question 7

Which of the following is a direct consequence of Avogadro’s Law?

Accepted Answer

Equal volumes of any ideal gas at the same temperature and pressure contain equal numbers of particles.

Question 8

A sample of acetylene ($$\mathrm{C_2H_2}) is $$collected over water at 23°C. The total pressure is 738 torr, and the vapor pressure of water is 21 torr. What is the pressure of the dry acetylene gas?

Accepted Answer

$$717\ 	ext{torr}$$

Question 9

Which of the following conditions would cause a real gas to deviate most from ideal behavior?

Accepted Answer

Low temperature and high pressure

Question 10

A chemist isolates a gas in a 0.213 L flask at 100.0°C and 754 torr. The mass of the gas is 0.582 g. What is the molar mass of the gas? ($$R = 0.0821\ 	ext{L} \cdot 	ext{atm} / 	ext{mol} \cdot 	ext{K}$$, $$1\ 	ext{atm} = 760\ 	ext{torr})$$

Accepted Answer

$$84.4\ 	ext{g/mol}$$

Question 11

Which equation would you use to calculate the density of a gas at non-standard conditions?

Accepted Answer

$$d = \frac{PM}{RT}$$

Question 12

A reaction produces hydrogen gas that is collected over water at 25°C. If the total pressure is 765 torr and the vapor pressure of water is 24 torr, what is the pressure of the hydrogen gas?

Accepted Answer

$$741\ 	ext{torr}$$

Question 13

Which of the following best explains why gases are compressible but liquids and solids are not?

Accepted Answer

Gas particles are far apart with much empty space between them.

Question 14

A 35.5 g sample of copper(II) oxide reacts with hydrogen gas to form copper and water. What volume of hydrogen gas at 765 torr and 225°C is needed? ($$	ext{CuO} + 	ext{H}_2 ightarrow 	ext{Cu} + 	ext{H}_2	ext{O}$$, $$M_{	ext{CuO}} = 79.55\ 	ext{g/mol}$$, $$R = 0.0821\ 	ext{L} \cdot 	ext{atm} / 	ext{mol} \cdot 	ext{K})$$

Accepted Answer

$$13.2\ 	ext{L}$$

Question 15

Which of the following is NOT an assumption of the kinetic-molecular theory for ideal gases?

Accepted Answer

Gas particles exert attractive and repulsive forces on each other.

Question 16

If the temperature of a fixed amount of gas is doubled at constant pressure, what happens to the volume?

Accepted Answer

It doubles.

Question 17

Which of the following best describes Dalton’s Law of Partial Pressures?

Accepted Answer

The total pressure of a mixture of gases is the sum of the partial pressures of each gas.

Question 18

A gas occupies 5.0 L at 1.0 atm and 273 K. If the pressure is increased to 2.0 atm and the temperature to 546 K, what is the new volume?

Accepted Answer

$$5.0\ 	ext{L}$$

Gases and the Kinetic-Molecular Theory: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards