$$K_w = [H^+][OH^-] = 1.0 \times 10$$^{-14}$$

Question 1

Which statement best describes dynamic equilibrium in a reversible chemical reaction?

Accepted Answer

The rates of the forward and reverse reactions are equal, and the concentrations of reactants and products remain constant over time.

Question 2

For the reaction $$\mathrm{N_2$(g) + 3H_2(g) \rightleftharpoons 2NH_3(g)}$$, the equilibrium constant expression $$K_c is$$:

Accepted Answer

$$K_c = \dfrac{[NH_3$]^2}{[N_2$][H_2$]^3}$$

Question 3

If $$K$$ for a reaction is much greater than 1, what does this indicate about the equilibrium mixture?

Accepted Answer

Products are favored at equilibrium.

Question 4

Which of the following will NOT affect the value of the equilibrium constant $$K$$ for a given reaction?

Accepted Answer

Adding a catalyst.

Question 5

For the reaction $$\mathrm{2SO_2(g) + O_2$(g) \rightleftharpoons 2SO_3(g)}$$, if $$Q \u003c K$$, what will happen?

Accepted Answer

The reaction will shift toward the products.

Question 6

Which statement correctly describes Le Châtelier's principle?

Accepted Answer

If a system at equilibrium is disturbed, it will shift to minimize the disturbance and restore equilibrium.

Question 7

A buffer solution is prepared by mixing acetic acid and sodium acetate. Which equation can be used to calculate its pH?

Accepted Answer

$$\mathrm{pH = pK_a + \log\left(\dfrac{[A^-]}{[HA]}\right)}$$

Question 8

Which of the following best describes the difference between a strong acid and a weak acid?

Accepted Answer

A strong acid ionizes completely in water, while a weak acid ionizes only partially.

Question 9

Which of the following is true for the ion product constant for water, $$K_w$$, at 25°C?

Accepted Answer

$$K_w = [H^+][OH^-] = 1.0 	imes 10$$^{-14}$$

Question 10

A solution has $$[H^+] = 2.5 	imes 10$$^{-5}$$ M. What is its pH?

Accepted Answer

$$pH = 4.60$$

Question 11

Which of the following is a characteristic of a Lewis acid?

Accepted Answer

It accepts an electron pair.

Question 12

Which of the following best describes the common ion effect?

Accepted Answer

The addition of a common ion decreases the solubility of a salt.

Question 13

During a titration of a weak acid with a strong base, which point on the titration curve corresponds to the equivalence point?

Accepted Answer

Where the amount of acid equals the amount of base added.

Question 14

Which of the following is the correct expression for the solubility product constant, $$K_{sp}$$, for $$\mathrm{$$CaF_2$$}$$?

Accepted Answer

$$K_{sp} = [Ca$$^{2+}$$][F^-]^2$$

Question 15

A buffer solution is most effective when:

Accepted Answer

The concentrations of acid and conjugate base are approximately equal.

Question 16

Which of the following will increase the solubility of $$\mathrm{AgCl} in $$water?

Accepted Answer

Adding $$\mathrm{NH_3$}$$, which forms a complex ion with $$\mathrm{Ag^+}.$$

Question 17

Which of the following is true for a polyprotic acid?

Accepted Answer

It can donate more than one proton per molecule.

Question 18

If the reaction quotient $$Q$$ for a saturated solution of $$\mathrm{$$BaSO_4$$} is $$greater than $$K_{sp}$$, what will happen?

Accepted Answer

Precipitation of $$\mathrm{$$BaSO_4$$}$$ will occur.

Question 19

Which of the following is the correct relationship between pH and pOH at 25°C?

Accepted Answer

$$pH + pOH = 14$$

General Chemistry Study Guide: Chemical Equilibrium, Acids & Bases, and Aqueous Ionic Equilibria

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