Question 1

Which of the following is NOT an intermolecular force?

Accepted Answer

Electrostatic attractions between ion pairs

Question 2

Which statement best explains why the boiling point of water ($$H_2O) is $$much higher than that of methane ($$CH_4$$), even though their molar masses are similar?

Accepted Answer

Water molecules form strong hydrogen bonds, while methane molecules only experience London dispersion forces.

Question 3

Which of the following molecules would you expect to have the highest boiling point?

Accepted Answer

Methanol ($$CH_3OH)$$

Question 4

A sample of water is placed in a 250-mL beaker with a 7-cm diameter at $$55\ ^\circ C. $$Which factor most increases the rate of vaporization compared to a 100-mL beaker at $$25\ ^\circ C$$?

Accepted Answer

Both higher temperature and larger surface area increase the rate of vaporization.

Question 5

Which of the following best describes London dispersion forces?

Accepted Answer

They are present in all molecules, regardless of polarity.

Question 6

Rank the following substances in order of increasing boiling point: $$Ne$$, $$CO_2$$, $$HF$$, $$BaCl_2$$, $$H_2.$$

Accepted Answer

$$H_2$$ \u003c Ne \u003c $$CO_2$$ \u003c HF \u003c $$BaCl_2$$

Question 7

Which of the following molecules can exhibit hydrogen bonding?

Accepted Answer

Ammonia ($$NH_3)$$

Question 8

What happens to the vapor pressure of a liquid when its surface area is increased at constant temperature?

Accepted Answer

The vapor pressure remains the same.

Question 9

Which of the following best explains why n-octane ($$C_8H_{18}) $$has a higher boiling point than n-hexane ($$C_6H_{14}$$)?

Accepted Answer

n-Octane has more electrons and a larger surface area, leading to stronger London dispersion forces.

Question 10

Which of the following is the strongest type of intermolecular force present in pure water ($$H_2O$$)?

Accepted Answer

Hydrogen bonding

Question 11

A solution contains sodium chloride ($$NaCl) $$dissolved in water. What is the primary intermolecular force between the $$Na^+$$ ions and water molecules?

Accepted Answer

Ion-dipole interactions

Question 12

Which of the following statements about intermolecular and intramolecular forces is correct?

Accepted Answer

Intramolecular forces are generally much stronger than intermolecular forces.

Question 13

Which of the following molecules would have the strongest London dispersion forces?

Accepted Answer

Iodine ($$I_2)$$

Question 14

Which of the following best describes the boiling point of a liquid?

Accepted Answer

The temperature at which the vapor pressure of the liquid equals the external pressure.

Question 15

Which of the following would increase the boiling point of a molecule the most?

Accepted Answer

Attaching an $$-OH$$ group to the molecule

Question 16

Which of the following substances would you expect to have the lowest vapor pressure at room temperature?

Accepted Answer

Water ($$H_2O)$$

Question 17

Which of the following best explains why branching in alkanes lowers their boiling point?

Accepted Answer

Branching decreases surface area, reducing the strength of London dispersion forces.

Question 18

Which of the following is a real-life example of ion-dipole interactions?

Accepted Answer

Dissolving table salt ($$NaCl) in $$water

Question 19

Which of the following molecules would you expect to have the greatest rate of vaporization at $$25\ ^\circ C$$?

Accepted Answer

Methane ($$CH_4)$$

Question 20

Which of the following best describes the relationship between intermolecular forces and vapor pressure?

Accepted Answer

Stronger intermolecular forces result in lower vapor pressure.

Liquids, Solids, and Intermolecular Forces: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard