Q: A 2.0 L container holds 0.5 mol of an ideal gas at 300 K. What is the pressure inside the container? (Use $$R = 0.0821\ \text{L}\cdot\text{atm}/\text{mol}\cdot\text{K})$$

$$P = \frac{nRT}{V} = \frac{0.5 \times 0.0821 \times 300}{2.0} = 6.16\ \text{atm}$$

Q: Which scenario best illustrates an ion-dipole interaction?

A sodium ion ($$\text{Na}^+) $$surrounded by water molecules with the oxygen atoms pointing toward the ion.

Q: Which molecule would have the strongest London dispersion forces?

$$\text{C}_8\text{H}_{18} ($$octane)

Question 1

Which of the following best describes the origin of pressure in a gas sample?

Accepted Answer

Pressure arises from the collisions of gas particles with the walls of the container, transferring momentum.

Question 2

A 2.0 L container holds 0.5 mol of an ideal gas at 300 K. What is the pressure inside the container? (Use $$R = 0.0821\ 	ext{L}\cdot	ext{atm}/	ext{mol}\cdot	ext{K})$$

Accepted Answer

$$P = \frac{nRT}{V} = \frac{0.5 	imes 0.0821 	imes 300}{2.0} = 6.16\ 	ext{atm}$$

Question 3

According to the kinetic molecular theory, which statement is true about the relationship between temperature and the average kinetic energy of gas particles?

Accepted Answer

The average kinetic energy increases linearly with temperature.

Question 4

Which gas will have the highest average speed at the same temperature: $$	ext{O}_2$$, $$	ext{N}_2$$, $$	ext{CO}_2$$, or $$	ext{He}$$?

Accepted Answer

$$	ext{He}$$

Question 5

A sample of gas undergoes a decrease in volume while the temperature and number of moles remain constant. What happens to the pressure?

Accepted Answer

Pressure increases because it is inversely proportional to volume.

Question 6

Which intermolecular force is strongest?

Accepted Answer

Ion-Ion interactions

Question 7

Which of the following molecules can form hydrogen bonding interactions?

Accepted Answer

$$	ext{NH}_3$$

Question 8

Which property increases as the strength of intermolecular forces increases?

Accepted Answer

Boiling point

Question 9

Which scenario best illustrates an ion-dipole interaction?

Accepted Answer

A sodium ion ($$	ext{Na}^+) $$surrounded by water molecules with the oxygen atoms pointing toward the ion.

Question 10

Which variable most strongly affects the strength of temporary dipole-induced dipole (London dispersion) forces?

Accepted Answer

Polarizability, which increases with molecular size and shape.

Question 11

Which of the following conditions causes a gas to behave less ideally?

Accepted Answer

High pressure and low temperature

Question 12

Which of the following best describes effusion?

Accepted Answer

The movement of gas particles through a tiny hole into a vacuum.

Question 13

Which molecule would have the strongest London dispersion forces?

Accepted Answer

$$	ext{C}_8	ext{H}_{18} ($$octane)

Question 14

A phase diagram shows the triple point, critical point, and regions for solid, liquid, and gas. What is the triple point?

Accepted Answer

The temperature and pressure at which all three phases coexist in equilibrium.

Question 15

Which of the following statements about dipole-dipole interactions is correct?

Accepted Answer

They occur between molecules with permanent dipoles, aligning positive and negative ends.

Question 16

If the molecular mass of gas A is twice that of gas B, how do their average speeds compare at the same temperature?

Accepted Answer

Gas B has a speed $$\sqrt{2}$$ times greater than gas A.

Question 17

Which of the following best explains why water has a higher boiling point than methane?

Accepted Answer

Water forms hydrogen bonds, which are stronger than the London dispersion forces in methane.

Question 18

A gas sample is compressed from 4.0 L to 2.0 L at constant temperature. If the initial pressure was 1.0 atm, what is the final pressure?

Accepted Answer

$$P_2$$ = $$P_1$$ \frac{$$V_1$$}{$$V_2$$} = 1.0 	imes \frac{4.0}{2.0} = 2.0\ 	ext{atm}$$

Question 19

Which of the following is NOT a factor that increases the strength of charge-charge interactions between molecules?

Accepted Answer

Greater distance between molecules

Study Guide: Gases, Liquids, and Intermolecular Forces (IMFs)

Study Guide - Practice Questions

Study Guide - Flashcards