Q: A solution has a pH of 3. What is the $$[H^+]$$ concentration?

$$[H^+] = 1 \times 10$$^{-3}$$ M

Q: Which of the following is true for a neutral solution at 25°C?

$$[H^+] = [OH^-] = 1 \times 10$$^{-7}$$ M

Q: Which of the following is the correct formula for calculating percent dissociation of an acid?

$$\% \text{ dissociation} = \dfrac{\text{amount dissociated (mol/L)}}{\text{total amount of HA (mol/L)}} \times 100$$

Q: If the $$K_a of$$ $$CH_3COOH is$$ $$1.8 \times 10$$^{-5}$$ and the K_a$ of HF$ is 7.2$$ \times $$10^{-4}$$, what is the equilibrium constant $$K$$ for the reaction $$CH_3COOH + F^- \rightleftharpoons HF + CH_3COO^-$$?

$$K = \dfrac{7.2 \times 10$$^{-4}$$}{1.8 \times 10$$^{-5}$$}$$

Question 1

Which of the following best describes a Lewis acid?

Accepted Answer

A lone-pair acceptor

Question 2

Given the reaction $$HA + H_2O \rightleftharpoons A^- + H_3O^+$$, which species is the conjugate base?

Accepted Answer

$$A^-$$

Question 3

What is the equilibrium constant expression for the dissociation of a generic acid $$HA in $$water?

Accepted Answer

$$K_a = \dfrac{[H^+][A^-]}{[HA]}$$

Question 4

Which statement is true regarding acid strength and $$K_a$$?

Accepted Answer

A strong acid has a $$K_a$$ much greater than 1

Question 5

Which of the following acids is the strongest based on the $$K_a$$ values below?

$$HCl$$: very large
$$HF$$: $$7.2 	imes 10$$^{-4}$$
CH_3$$COOH$$: 1.8$$ 	imes $$10^{-5}$$
$$H_2CO_3$$: $$4.3 	imes 10$$^{-7}$$

Accepted Answer

$$HCl$$

Question 6

If $$HA is a $$stronger acid than $$H_3O^+$$, what is the value of $$K_a$$ for $$HA$$?

Accepted Answer

$$K_a \u003e 1$$

Question 7

What is the value of the equilibrium constant $$K$$ for the auto-ionization of water at 25°C?

Accepted Answer

$$K \u003c 1$$

Question 8

At 25°C, what is the value of $$K_w$$ for water?

Accepted Answer

$$K_w = 1 	imes 10$$^{-14}$$

Question 9

What is the pH of a solution with $$[H^+] = 1.0 	imes 10$$^{-5}$$ M?

Accepted Answer

pH = 5

Question 10

A solution has a pH of 3. What is the $$[H^+]$$ concentration?

Accepted Answer

$$[H^+] = 1 	imes 10$$^{-3}$$ M

Question 11

Which of the following is true for a neutral solution at 25°C?

Accepted Answer

$$[H^+] = [OH^-] = 1 	imes 10$$^{-7}$$ M

Question 12

Which of the following statements about the pH scale is correct?

Accepted Answer

A solution with pH = 7 is neutral

Question 13

A 0.10 M solution of HCl is prepared. What is the pH?

Accepted Answer

pH = 1

Question 14

A 0.10 M solution of CH$$_3$$COOH (acetic acid) has $$K_a = 1.8 	imes 10$$^{-5}$$. Which type of problem is this?

Accepted Answer

Equilibrium problem

Question 15

Which of the following is the correct formula for calculating percent dissociation of an acid?

Accepted Answer

$$\% 	ext{ dissociation} = \dfrac{	ext{amount dissociated (mol/L)}}{	ext{total amount of HA (mol/L)}} 	imes 100$$

Question 16

Which of the following is NOT a correct definition of a base?

Accepted Answer

A $$H^+ ($$proton) donor (Bronsted-Lowry)

Question 17

Which of the following 0.1 M solutions will be neutral?

Accepted Answer

NaCl

Question 18

Which of the following 0.1 M solutions has the highest pH?

Accepted Answer

KCN

Question 19

If the $$K_a of$$ $$CH_3COOH is$$ $$1.8 	imes 10$$^{-5}$$ and the K_a$ of HF$ is 7.2$$ 	imes $$10^{-4}$$, what is the equilibrium constant $$K$$ for the reaction $$CH_3COOH + F^- ightleftharpoons HF + CH_3COO^-$$?

Accepted Answer

$$K = \dfrac{7.2 	imes 10$$^{-4}$$}{1.8 	imes 10$$^{-5}$$}$$

Chapter 17: Acids & Bases – General Chemistry Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard