E-3 Equilibria of Acids/Bases

Question 1

Complete the formula

pH + pOH =

Answer 1

14

Question 2

Complete the following equation

K_w =

Answer 2

[H₃O⁺][OH^-] = 1.00 x 10^-14

Question 3

Complete the following equation.

K_a•K_b =

Answer 3

1.0 x 10^-14

Question 4

Don’t use a calculator!

What is the pH of a when [H₃O⁺] = 1.0 x 10^-3 M?

Answer 4

3

Question 5

Don’t use a calculator!

What is the pH of a when [H₃O⁺] = 1.0 x 10^-7 M?

Answer 5

7

Question 6

Don’t use a calculator!

What is the pH of a when [H₃O⁺] = 1.0 x 10^-13 M?

Answer 6

13

Question 7

Don’t use a calculator!

What is the pOH of a when [OH^-] = 1.0 x 10^-11 M?

Answer 7

11

Question 8

Don’t use a calculator!

What is the pOH of a when [OH^-] = 1.0 x 10^-5 M?

Answer 8

5

Question 9

Don’t use a calculator!

What is the pOH of a when [OH^-] = 1.0 x 10^-7 M?

Answer 9

7

Question 10

Don’t use a calculator!

What is the pH of a when [OH^-] = 1.0 x 10^-2 M?

Answer 10

14 - 2 = 12

Question 11

Don’t use a calculator!

What is the pH of a when [OH^-] = 1.0 x 10^-9 M?

Answer 11

14 - 9 = 5

Question 12

Don’t use a calculator!

What is the pH of a when [OH^-] = 1.0 x 10^-7 M?

Answer 12

14 - 7 = 7

Question 13

Don’t use a calculator!

The K_a of an acid is 1.0 x 10^-4. What is the K_b of its conjugate base?

Answer 13

1.0 x 10^-14 / 1.0 x 10^-4 = 1.0 x 10^-10

Question 14

Don’t use a calculator!

The K_a of an acid is 1.0 x 10^-12. What is the K_b of its conjugate base?

Answer 14

1.0 x 10^-14 / 1.0 x 10^-12 = 1.0 x 10^-2

Question 15

Don’t use a calculator!

The Kb of a base is 1.0 x 10^-5. What is the Ka of its conjugate acid?

Answer 15

1.0 x 10^-14 / 1.0 x 10^-5 = 1.0 x 10^-9

Question 16

Don’t use a calculator!

The Kb of a base is 1.0 x 10^-8. What is the Ka of its conjugate acid?

Answer 16

1.0 x 10^-14 / 1.0 x 10^-8 = 1.0 x 10^-6

Question 17

Write out the Bronsted-Lowry Reaction for nitrous acid (HNO₂).

Answer 17

HNO₂ + H₂O ⇔ NO₂^- + H₃O⁺

Question 18

Write out the Bronsted-Lowry Reaction for methyl amine (CH₃NH₂).

Answer 18

CH₃NH₂ + H₂O ⇔ CH₃NH₃⁺ + OH^-

Question 19

Write out the Bronsted-Lowry Reaction for the hydrogen sulfate ion (HSO^₄-) acting as a base.

Answer 19

HSO₄^- + H₂O ⇔ H₂SO₄ + OH^-

Question 20

Write out the Bronsted-Lowry Reaction for the hydrogen sulfate ion (HSO^₄-) acting as an acid.

Answer 20

HSO₄^- + H₂O ⇔ SO₄^2- + H_{<span>3</span>}O⁺

Question 21

Write out the law of mass action for the following reaction.

HF + H₂O ⇔ F^-+ H₃O⁺

Answer 21

K_a = [F^-][H₃O⁺] / [HF]

Question 22

Write out the law of mass action for the following reaction.

F^- + H₂O ⇔ HF⁺ OH^-

Answer 22

K_b = [HF][OH^-] / [F^-]

Question 23

What is the conjugate base of HF?

HF + H₂O ⇔ F^-+ H₃O⁺

Answer 23

F^-

Question 24

What is the conjugate acid of H₂O?

HF + H₂O ⇔ F^-+ H₃O⁺

Answer 24

H₃O⁺

Question 25

What is the conjugate acid of CH₃NH₂?

CH₃NH₂ + H₂O ⇔ CH₃NH₃⁺ + OH^-

Answer 25

CH₃NH₃⁺

Question 26

What is the conjugate acid of acetate ion (C₂H₃O₂^-)?

Answer 26

HC₂H₃O₂

Question 27

What is the conjugate base of HCN?

Answer 27

CN^-

Question 28

What is the conjugate base of HSO₄^-?

Answer 28

SO₄^2-

Question 29

What is the conjugate acid of HSO₄^-?

Answer 29

H₂SO₄

Question 30

acid, base, or neutral

H₂SO₃

Answer 30

acid

Question 31

acid, base, or neutral

NH₃

Answer 31

Base

Question 32

acid, base, or neutral

LiCl

Answer 32

Neutral

Question 33

acid, base, or neutral

NH₄Br

Answer 33

acid

Question 34

acid, base, or neutral

NaClO

Answer 34

base

Question 35

acid, base, or neutral

FeCl₃

Answer 35

acid

Question 36

acid, base, or neutral

NaHSO₃

Answer 36

acid

Question 37

acid, base, or neutral

Na₂SO₃

Answer 37

base

Question 38

acid, base, or neutral

Ba(OH)₂

Answer 38

base

Question 39

acid, base, or neutral

KI

Answer 39

Neutral