Question 1

Which of the following molecules exhibits hydrogen bonding as its strongest intermolecular force?

Accepted Answer

NH$$_3$$

Question 2

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 3

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

Accepted Answer

The solubility decreases because gas molecules escape more easily.

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 compounds would you expect to have the highest boiling point?

Accepted Answer

H$$_2O$$

Question 6

A reaction has a 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 four.

Question 7

Which of the following is a colligative property?

Accepted Answer

Boiling-point elevation

Question 8

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

Accepted Answer

$$i = 3$$

Question 9

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 10

A catalyst increases the rate of a chemical reaction by:

Accepted Answer

Decreasing the activation energy.

Question 11

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 12

Which of the following best describes the relationship between intermolecular force strength and boiling point?

Accepted Answer

Stronger intermolecular forces lead to higher boiling points.

Question 13

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 14

Which of the following is true about the entropy of a system?

Accepted Answer

Higher entropy is more favorable.

Question 15

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 16

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

Accepted Answer

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

Question 17

If the rate constant $$k$$ for a reaction increases when temperature increases, which equation best describes this relationship?

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 the effect of a catalyst on the activation energy ($$E_a) of a $$reaction?

Accepted Answer

It lowers the activation energy.

Question 19

Which of the following is the correct formula for mass percent?

Accepted Answer

$$\frac{	ext{mass component}}{	ext{mass solution}} 	imes 100\%$$

Question 20

Which of the following best describes the effect of increasing pressure on the solubility of a gas in a liquid?

Accepted Answer

The solubility increases.

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

Guida di studio - Domande di pratica

Study guide - Flashcard