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 exhibits hydrogen bonding as its strongest 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

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

Question 4

Which of the following best describes a saturated solution?

Accepted Answer

A solution in which no more solute can dissolve at a given temperature.

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

$$\chi = \frac{2.0}{10.0}$$

Question 6

Which of the following statements about entropy is correct?

Accepted Answer

Higher entropy is more favorable for mixing.

Question 7

Which of the following best explains why NaCl dissolves in water but not in hexane (C\_6H\_{14})?

Accepted Answer

NaCl forms ion-dipole interactions with water, but not with hexane.

Question 8

A reaction has the following rate law: $$	ext{Rate} = k[NO_2$]^2. If $$the concentration of NO\_2 is doubled, how does the rate change?

Accepted Answer

The rate increases by a factor of 4.

Question 9

Which of the following is a colligative property?

Accepted Answer

Boiling-point elevation

Question 10

What is the van’t Hoff factor ($$i) $$for a solution of CaCl\_2, assuming complete dissociation?

Accepted Answer

$$i = 3$$

Question 11

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

$$M = \frac{5.00}{180.16} \div 0.100 = 0.278 M$$

Question 12

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

Accepted Answer

A catalyst decreases the activation energy, increasing the reaction rate.

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

Which of the following factors does NOT affect the rate of a chemical reaction?

Accepted Answer

Color of the reactants

Question 15

A reaction is found to be first order in A and zero order in B. What is the rate law for this reaction?

Accepted Answer

$$	ext{Rate} = k[A]$$

Question 16

Which of the following best describes the effect of increasing temperature on the solubility of a gas in water?

Accepted Answer

The solubility decreases.

Question 17

Which of the following is the correct form of the Arrhenius equation for comparing rate constants at two temperatures?

Accepted Answer

$$\ln \frac{k_1$}{k_2$} = \frac{E_a}{R} (\frac{1}{T_2$} - \frac{1}{T_1$})$$

Question 18

Which of the following best describes a supersaturated solution?

Accepted Answer

A solution that contains more dissolved solute than it can theoretically hold at a given temperature.

Question 19

Which of the following is the strongest type of intermolecular force present in liquid H\_2O?

Accepted Answer

Hydrogen bonding

Question 20

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

Accepted Answer

The rate constant increases.

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

Guida di studio - Domande di pratica

Study guide - Flashcard