1) A solution of perchloric acid is prepared that has a molar concentration equal to the fourth and fifth digits of your Student ID Number divided by 105. What are the hydronium ion and hydroxide ion concentrations in that solution at 25 °C?
2) A solution of nitric acid is prepared that has a molar concentration equal to the fourth and fifth digits of your Student ID Number divided by 104. What are the hydronium ion and hydroxide ion concentrations in that solution at 25 °C?
3) A solution of potassium hydroxide is prepared that has a molar concentration equal to the fourth and fifth digits of your Student ID Number divided by 103. What are the hydronium ion and hydroxide ion concentrations in that solution at 25 °C?
4) A solution of barium hydroxide is prepared that has a molar concentration equal to the fourth and fifth digits of your Student ID Number divided by 105. What are the hydronium ion and hydroxide ion concentrations in that solution at 25 °C? Assume complete solubility and complete ionization.
1) For perchloric acid:
HClO4(aq) + H2O(l) → H3O+(aq) + ClO4–(aq)
So the [H3O+] = [HClO4] = ID/105 M
[OH–] = 1.0×10–14/[H3O+]
2) For nitric acid:
HNO3(aq) + H2O(l) → H3O+(aq) + NO3–(aq)
So the [H3O+] = [HNO3] = ID/104 M
[OH–] = 1.0×10–14/[H3O+]
3) For potassium hydroxide:
KOH(aq) → K+(aq) + OH–(aq)
So [OH–] = [KOH] = ID/103 M
[H3O+] = 1.0×10–14/[OH–]
4) For barium hydroxide:
Ba(OH)2(aq) → Ba2+(aq) + 2 OH–(aq)
So [OH–] = 2×[Ba(OH)2] = 2×ID/105 M
[H3O+] = 1.0×10–14/[OH–]
Specific answers:
| Question 1 | Question 2 | Question 3 | Question 4 | ||||||||
| [HClO4] (M) | [H3O+] (M) | [OH–] (M) | [HNO3] (M) | [H3O+] (M) | [OH–] (M) | [KOH] (M) | [H3O+] (M) | [OH–] (M) | [Ba(OH)2} (M) | [H3O+] (M) | [OH–] (M) |
| 0.00050 | 5.0×10–4 | 2.0×10–11 | 0.0050 | 5.0×10–3 | 2.0×10–12 | 0.050 | 2.0×10–13 | 5.0×10–2 | 0.00050 | 1.0×10–11 | 1.0×10–3 |
| 0.00052 | 5.2×10–4 | 1.9×10–11 | 0.0052 | 5.2×10–3 | 1.9×10–12 | 0.052 | 1.9×10–13 | 5.2×10–2 | 0.00052 | 1.0×10–11 | 1.0×10–3 |
| 0.00054 | 5.4×10–4 | 1.9×10–11 | 0.0054 | 5.4×10–3 | 1.9×10–12 | 0.054 | 1.9×10–13 | 5.4×10–2 | 0.00054 | 9.3×10–12 | 1.1×10–3 |
| 0.00055 | 5.5×10–4 | 1.8×10–11 | 0.0055 | 5.5×10–3 | 1.8×10–12 | 0.055 | 1.8×10–13 | 5.5×10–2 | 0.00055 | 9.1×10–12 | 1.1×10–3 |
| 0.00056 | 5.6×10–4 | 1.8×10–11 | 0.0056 | 5.6×10–3 | 1.8×10–12 | 0.056 | 1.8×10–13 | 5.6×10–2 | 0.00056 | 8.9×10–12 | 1.1×10–3 |
| 0.00057 | 5.7×10–4 | 1.8×10–11 | 0.0057 | 5.7×10–3 | 1.8×10–12 | 0.057 | 1.8×10–13 | 5.7×10–2 | 0.00057 | 8.8×10–12 | 1.1×10–3 |
| 0.00058 | 5.8×10–4 | 1.7×10–11 | 0.0058 | 5.8×10–3 | 1.7×10–12 | 0.058 | 1.7×10–13 | 5.8×10–2 | 0.00058 | 8.6×10–12 | 1.2×10–3 |
| 0.00059 | 5.9×10–4 | 1.7×10–11 | 0.0059 | 5.9×10–3 | 1.7×10–12 | 0.059 | 1.7×10–13 | 5.9×10–2 | 0.00059 | 8.5×10–12 | 1.2×10–3 |
| 0.00060 | 6.0×10–4 | 1.7×10–11 | 0.0060 | 6.0×10–3 | 1.7×10–12 | 0.060 | 1.7×10–13 | 6.0×10–2 | 0.00060 | 8.3×10–12 | 1.2×10–3 |
| 0.00061 | 6.1×10–4 | 1.6×10–11 | 0.0061 | 6.1×10–3 | 1.6×10–12 | 0.061 | 1.6×10–13 | 6.1×10–2 | 0.00061 | 8.2×10–12 | 1.2×10–3 |
| 0.00062 | 6.2×10–4 | 1.6×10–11 | 0.0062 | 6.2×10–3 | 1.6×10–12 | 0.062 | 1.6×10–13 | 6.2×10–2 | 0.00062 | 8.1×10–12 | 1.2×10–3 |
| 0.00063 | 6.3×10–4 | 1.6×10–11 | 0.0063 | 6.3×10–3 | 1.6×10–12 | 0.063 | 1.6×10–13 | 6.3×10–2 | 0.00063 | 7.9×10–12 | 1.3×10–3 |