Question 1

Which of the following statements best describes the relationship between intermolecular forces and the boiling point of a substance?

Accepted Answer

Substances with stronger intermolecular forces generally have higher boiling points.

Question 2

Which of the following molecules would exhibit hydrogen bonding as the predominant intermolecular force?

Accepted Answer

NH$$_3$$

Question 3

A solution is prepared by dissolving 10.0 g of NaCl (molar mass = 58.44 g/mol) in 100.0 g of water. What is the molality ($$m) of $$the solution?

Accepted Answer

$$m = \frac{10.0/58.44}{0.100} = 1.71$$ mol/kg

Question 4

Which of the following best describes a saturated solution?

Accepted Answer

A solution in which the rate of dissolving equals the rate of crystallization.

Question 5

Which of the following is the correct expression for the mole fraction ($$\chi) of $$ethanol in a solution containing 2.0 mol ethanol and 8.0 mol water?

Accepted Answer

$$\chi = \frac{2.0}{2.0 + 8.0}$$

Question 6

Which of the following statements about entropy is correct?

Accepted Answer

Higher entropy is more favorable for mixing solutions.

Question 7

Which of the following best describes the effect of a catalyst on a chemical reaction?

Accepted Answer

A catalyst decreases the activation energy and increases the reaction rate.

Question 8

Given the reaction: $$2NO_2(g) \rightarrow 2NO(g) + O_2$(g)$$, which of the following is the correct rate expression in terms of the disappearance of $$NO_2$$?

Accepted Answer

Rate $$= -\frac{1}{2} \frac{\Delta [NO_2$]}{\Delta t}$$

Question 9

Which of the following is true regarding the solubility of gases in liquids?

Accepted Answer

The solubility of gases increases with increasing pressure.

Question 10

A solution is made by dissolving 5.00 g of glucose (C$$_6H$_{12}O$_6$$, molar mass = 180.16 g/mol) in enough water to make 100.0 mL of solution. What is the molarity ($$M) of $$the solution?

Accepted Answer

$$M = \frac{5.00/180.16}{0.1000} = 0.278 M$$

Question 11

Which of the following best describes the term 'miscible'?

Accepted Answer

Two substances that mix in all proportions to form a homogeneous solution.

Question 12

Which of the following is the strongest type of intermolecular force?

Accepted Answer

Ion-dipole interactions

Question 13

Which of the following is the correct integrated rate law for a first-order reaction?

Accepted Answer

$$\ln[A] = -kt + \ln[A]_0$$

Question 14

A reaction has a rate law: Rate $$= k[NO_2$]^2. If $$the concentration of $$NO_2 is $$doubled, how does the rate change?

Accepted Answer

The rate increases by a factor of four.

Question 15

Which of the following is the correct formula for calculating the freezing-point depression of a solution?

Accepted Answer

$$\Delta T_f = iK_f m$$

Question 16

Which of the following statements about the van’t Hoff factor ($$i) is $$correct?

Accepted Answer

$$i is $$greater than 1 for electrolytes because they dissociate into ions.

Question 17

Which of the following best explains why ionic compounds generally have higher melting points than molecular compounds?

Accepted Answer

Ionic bonds are stronger than intermolecular forces.

Question 18

Which of the following is a colligative property?

Accepted Answer

Boiling-point elevation

Question 19

A reaction has an activation energy ($$E_a) of 50.0 kJ/$$mol. If the temperature increases, what happens to the rate constant ($$k$$)?

Accepted Answer

$$k$$ increases

Question 20

Which of the following best describes the effect of temperature on the solubility of most solid solutes in water?

Accepted Answer

Solubility increases with increasing temperature.

Exam 1 Study Guide: Liquids, Solutions, and Chemical Kinetics

Guida di studio - Domande di pratica

Study guide - Flashcard