1. pH worksheet (#1)

2. 1. What is the pH of a solution with a hydrogen ion concentration of 1
1. What is the pH of a solution with a hydrogen ion concentration of 1.0 x 10-5 M?
pH = -log [H+] = - log (1.0 x 10-5 ) = 5

3. 2. What is the pH of a solution with a hydrogen ion concentration of 4
2. What is the pH of a solution with a hydrogen ion concentration of 4.5 x 10-8 M?
pH = -log [H+] = - log (4.5 x 10-8 ) =
7.34

4. 3. What is the pOH of a solution with a hydrogen ion concentration of 1.0 x 10-10 M?
pH = -log [H+] = - log (1.0 x ) = 10
Now use: pH + pOH = 14
14 – 10 = 4, so the pOH = 4

5. We need to use: pOH = - log [OH-]
4. What is the pOH of a solution with a hydroxide ion concentration of 1.0 x M?
We need to use: pOH = - log [OH-]
pOH = - log [1.0 x ]
pOH = 10

6. 5. What is the hydroxide ion concentration in a solution with a pH of 5?
pH = - log [ H+]
- pH = log [ H+]
10x (- pH) = 10x log [ H+]
10x (- 5) = 10x log [ H+]
10-5 = [ H+]
= 1.0 x M

7. This is our [H+], we need [OH-]
We need to use:
[H+] x [OH-] = 1.0 x M
[1.0 x M] x [OH-] = 1.0 x M
[1.0 x M]
[1.0 x M]
= 1.0 x 10 -9

8. 6. What is the hydrogen ion concentration in a solution with a pH of 9
pH = - log [ H+]
- pH = log [ H+]
10x (- pH) = 10x log [ H+]
10x (- 9.7) = 10x log [ H+]
= [ H+]
= 2.0 x M

9. 7. What is the hydronium ion concentration of a solution with a pH of 2.5?
pH = - log [ H+]
- pH = log [ H+]
10x (- pH) = 10x log [ H+]
10x (- 2.5) = 10x log [ H+]
= [ H+]
= 3.2 x M