Question 1

Which of the following best describes the main focus of thermochemistry as covered in General Chemistry II?

Accepted Answer

The study of the energy changes that accompany chemical reactions.

Question 2

A student mixes 50.0 mL of 1.0 M HCl with 50.0 mL of 1.0 M NaOH in a coffee-cup calorimeter. The temperature rises by 6.0°C. If the specific heat capacity of the solution is $$4.18 \ \mathrm{J} / (\mathrm{g} \cdot \mathrm{K})$$ and the density is $$1.00 \ \mathrm{g} / \mathrm{mL}$$, what is the enthalpy change ($$\Delta H) $$for the reaction per mole of water formed?

Accepted Answer

$$-50.2 \ \mathrm{kJ} / \mathrm{mol}$$

Question 3

Which of the following statements about entropy ($$S) is $$correct?

Accepted Answer

Entropy is a measure of the disorder or randomness of a system.

Question 4

A gas sample is compressed from 2.0 L to 1.0 L at constant temperature. According to the kinetic molecular theory, what happens to the pressure and why?

Accepted Answer

Pressure increases because the gas molecules collide with the walls more frequently.

Question 5

Which equation correctly relates the Gibbs free energy change ($$\Delta G) to $$enthalpy ($$\Delta H$$), entropy ($$\Delta S$$), and temperature ($$T$$)?

Accepted Answer

$$\Delta G = \Delta H - T\Delta S$$

Question 6

A reaction has $$\Delta H = +40 \ \mathrm{kJ}$$ and $$\Delta S = +100 \ \mathrm{J} / \mathrm{K}. At $$what temperature will the reaction become spontaneous?

Accepted Answer

$$T \u003e 400 \ \mathrm{K}$$

Question 7

Which of the following best explains why salt (NaCl) dissolves in water?

Accepted Answer

The hydration energy released when Na$$^+$$ and Cl$$^-$$ ions interact with water is greater than the lattice energy of NaCl.

Question 8

Which of the following is NOT a colligative property?

Accepted Answer

Molar absorptivity

Question 9

A solution is prepared by dissolving 10.0 g of glucose ($$C_6H_{12}O_6$) in 90.0 g of water. What is the mole fraction of glucose in the solution? (Molar mass of glucose = 180 g/mol, water = 18 g/mol)

Accepted Answer

0.010

Question 10

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

Accepted Answer

It lowers the activation energy, increasing the reaction rate.

Question 11

A reaction is first order in A and second order in B. Which rate law correctly represents this reaction?

Accepted Answer

$$	ext{rate} = k[A][B]^2$$

Question 12

Which of the following scenarios best illustrates Le Chatelier's Principle?

Accepted Answer

Increasing the temperature of an exothermic reaction shifts the equilibrium to the left.

Question 13

Which of the following is the correct expression for the equilibrium constant ($$K_c) $$for the reaction: $$2NO_2(g) \rightleftharpoons 2NO(g) + O_2$(g)$$?

Accepted Answer

$$K_c = \frac{[NO]^2[O_2$]}{[NO_2$]^2}$$

Question 14

A 0.10 M solution of a weak acid, HA, has a pH of 3.0. What is the acid dissociation constant ($$K_a) $$for HA?

Accepted Answer

$$1.0 	imes 10$$^{-5}$$

Question 15

Which of the following best explains why increasing the temperature generally increases the rate of a chemical reaction?

Accepted Answer

It increases the number of molecules with sufficient energy to overcome the activation barrier.

Question 16

Which of the following is a correct statement about colligative properties?

Accepted Answer

They depend only on the number of solute particles present.

Question 17

A sample of gas occupies 5.0 L at 1.0 atm and 300 K. What will be its volume at 2.0 atm and 300 K, assuming ideal gas behavior?

Accepted Answer

2.5 L

Question 18

Which of the following is the best example of a real-world application of chemical equilibrium?

Accepted Answer

The maintenance of blood pH in the human body through buffer systems.

Question 19

Which of the following is a correct statement about intermolecular forces?

Accepted Answer

London dispersion forces are present in all molecules, regardless of polarity.

Question 20

A solution is prepared by mixing 100 mL of 0.2 M NaCl and 100 mL of 0.2 M CaCl$$_2. $$What is the total concentration of chloride ions in the final solution?

Accepted Answer

0.60 M

General Chemistry II Syllabus and Study Guide

Study Guide - Practice Questions

Study Guide - Flashcards