$$[H^+] = 1.0 \times 10$$^{-12}$$\ \text{M}$$

$$K_w = 1.0 \times 10$$^{-14}$$

Hydrofluoric acid ($$K_a = 6.8 \times 10$$^{-4}$$)

$$[H^+] = 1.0 \times 10$$^{-12}$$\ \text{M}$$

Question 1

Which of the following statements best describes the Brønsted–Lowry definition of acids and bases?

Accepted Answer

Acids are proton donors, and bases are proton acceptors.

Question 2

A solution contains 0.010 M NaOH. What is the concentration of H+ ions in this solution at 25°C?

Accepted Answer

$$[H^+] = 1.0 	imes 10$$^{-12}$$\ 	ext{M}$$

Question 3

Which of the following acids is the strongest, based on molecular structure and electronegativity?

Accepted Answer

HClO4

Question 4

What is the pH of a solution with $$[H^+] = 1.0 	imes 10$$^{-3}$$\ 	ext{M}$$? (Use proper significant figures.)

Accepted Answer

$$	ext{pH} = 3.00$$

Question 5

Which of the following is an example of a weak acid?

Accepted Answer

HF

Question 6

A household cleaner contains ammonia (NH3). According to the Arrhenius definition, why is ammonia considered a base?

Accepted Answer

It produces OH– ions in water.

Question 7

Which of the following pairs are conjugate acid–base pairs?

Accepted Answer

NH3 and NH4+

Question 8

Which factor increases the strength of a binary acid (H–Y)?

Accepted Answer

Higher electronegativity of Y and weaker H–Y bond

Question 9

What is the value of the ion product constant of water ($$K_w) at 25$$°C?

Accepted Answer

$$K_w = 1.0 	imes 10$$^{-14}$$

Question 10

A student mixes 1 M HCl with water. What is the resulting concentration of H+ ions?

Accepted Answer

$$[H^+] = 1\ 	ext{M}$$

Question 11

Which of the following best explains why bases feel slippery?

Accepted Answer

Bases react with oils on the skin to form soap-like substances.

Question 12

Which acid has the highest acid ionization constant ($$K_a) $$among the following?

Accepted Answer

Hydrofluoric acid ($$K_a = 6.8 	imes 10$$^{-4}$$)

Question 13

Which of the following substances is amphoteric?

Accepted Answer

H2O

Question 14

A solution has a pH of 12. What is the concentration of H+ ions?

Accepted Answer

$$[H^+] = 1.0 	imes 10$$^{-12}$$\ 	ext{M}$$

Question 15

Which of the following is NOT a property of acids?

Accepted Answer

Feels slippery

Question 16

Which of the following reactions represents the autoionization of water?

Accepted Answer

$$H_2O(l) + H_2O(l) \rightleftharpoons H_3O^+(aq) + OH^-(aq)$$

Question 17

Which of the following is a real-life example of an organic acid found in fruits?

Accepted Answer

Citric acid

Question 18

A student adds acetic acid ($$CH_3COOH) to $$water. Which equation best represents its ionization?

Accepted Answer

$$CH_3COOH(aq) + H_2O(l) \rightleftharpoons CH_3COO^-(aq) + H_3O^+(aq)$$

Question 19

Which of the following best describes the relationship between pH and [H+]?

Accepted Answer

As pH increases, [H+] decreases by a factor of 10 for each unit.

Acids and Bases: Properties, Definitions, and Strength (General Chemistry Study Notes)

Study Guide - Practice Questions