Date Quiz 8-1 Acids and Bases pH
Name __________________________________________________ Period ________ Date ______________________ Quiz 8-1 Acids and Bases pH – Version 7
Total Points: _______/10
1. (a) Name the acid H3PO4. Phosphoric acid
(½ pt)
(b) Write the balanced dissociation equation for H3PO4 in an aqueous solution. 𝐻3 𝑃𝑂4 (𝑎𝑞) → 3 𝐻 + (𝑎𝑞) + 𝑃𝑂43− (𝑎𝑞) (c) Determine the [H+] in 0.130 M H3PO4.
(½ pt)
Answer (½ pt)
Show Work (1/4 pt)
Sigfigs (1/4 pt)
Ans & U (½ pt)
Work (1/4)
SF (1/4)
Ans & U (½ pt)
Work (1/4)
SF (1/4)
Work (1/4)
SF (1/4 pt)
𝐻3 𝑃𝑂4 (𝑎𝑞) → 3 𝐻 + (𝑎𝑞) + 𝑃𝑂43− (𝑎𝑞) 0.130 M 0.390 M 0.130 M [𝐻 + ] = 0.390 𝑀
(d) Calculate the pH of 0.130 M H3PO4. 𝑝𝐻 = −𝑙𝑜𝑔[𝐻 + ] = −𝑙𝑜𝑔(0.390) = 0.409 (e) Calculate the pOH of 0.130 M H3PO4. 𝑝𝐻 + 𝑝𝑂𝐻 = 14.00 𝑝𝑂𝐻 = 14.00 − 𝑝𝐻 = 14.00 − 0.409 = 13.591 (f) Calculate the [OH-] in 0.130 M H3PO4.
Ans & U (½ pt)
[𝑂𝐻 − ] = 10−𝑝𝑂𝐻 = 10−13.591 = 2.56 × 10−14 𝑀 2. (a) Write the chemical formula of sodium hydroxide. NaOH
(½ pt)
(b) Write the balanced dissociation equation for sodium hydroxide in an aqueous solution.
(½ pt)
𝑁𝑎𝑂𝐻(𝑎𝑞) → 𝑁𝑎+ (𝑎𝑞) + 𝑂𝐻 − (𝑎𝑞) (g) Determine the [H+] in sodium hydroxide pH 10.60
Ans & U (½ pt)
Work (1/4)
SF (1/4 pt)
Work (1/4)
SF (1/4 pt)
[𝐻 + ] = 10−𝑝𝐻 = 10−10.60 = 2.5 × 10−11 𝑀
(h) Calculate the pOH of sodium hydroxide pH 10.60 𝑝𝐻 + 𝑝𝑂𝐻 = 14.00 𝑝𝑂𝐻 = 14.00 − 𝑝𝐻 = 14.00 − 10.60 = 3.40
Ans & U (½ pt)
Name __________________________________________________ Period ________ Date ______________________
(i) Calculate the [OH-] in sodium hydroxide pH 10.60
Ans & U (½ pt)
Work (1/4)
SF (1/4 pt)
[𝑂𝐻 − ] = 10−𝑝𝑂𝐻 = 10−3.40 = 4.0 × 10−4 𝑀
3. When bromothymol blue is added to H3PO4 what color does it turn? yellow
(½ pt)
4. When bromothymol blue is added to a sodium hydroxide solution, what color does it turn? blue
(½ pt)
Total Points: _______/10
1. (a) Name the acid H3PO4. Phosphoric acid
(½ pt)
(b) Write the balanced dissociation equation for H3PO4 in an aqueous solution. 𝐻3 𝑃𝑂4 (𝑎𝑞) → 3 𝐻 + (𝑎𝑞) + 𝑃𝑂43− (𝑎𝑞) (c) Determine the [H+] in 0.130 M H3PO4.
(½ pt)
Answer (½ pt)
Show Work (1/4 pt)
Sigfigs (1/4 pt)
Ans & U (½ pt)
Work (1/4)
SF (1/4)
Ans & U (½ pt)
Work (1/4)
SF (1/4)
Work (1/4)
SF (1/4 pt)
𝐻3 𝑃𝑂4 (𝑎𝑞) → 3 𝐻 + (𝑎𝑞) + 𝑃𝑂43− (𝑎𝑞) 0.130 M 0.390 M 0.130 M [𝐻 + ] = 0.390 𝑀
(d) Calculate the pH of 0.130 M H3PO4. 𝑝𝐻 = −𝑙𝑜𝑔[𝐻 + ] = −𝑙𝑜𝑔(0.390) = 0.409 (e) Calculate the pOH of 0.130 M H3PO4. 𝑝𝐻 + 𝑝𝑂𝐻 = 14.00 𝑝𝑂𝐻 = 14.00 − 𝑝𝐻 = 14.00 − 0.409 = 13.591 (f) Calculate the [OH-] in 0.130 M H3PO4.
Ans & U (½ pt)
[𝑂𝐻 − ] = 10−𝑝𝑂𝐻 = 10−13.591 = 2.56 × 10−14 𝑀 2. (a) Write the chemical formula of sodium hydroxide. NaOH
(½ pt)
(b) Write the balanced dissociation equation for sodium hydroxide in an aqueous solution.
(½ pt)
𝑁𝑎𝑂𝐻(𝑎𝑞) → 𝑁𝑎+ (𝑎𝑞) + 𝑂𝐻 − (𝑎𝑞) (g) Determine the [H+] in sodium hydroxide pH 10.60
Ans & U (½ pt)
Work (1/4)
SF (1/4 pt)
Work (1/4)
SF (1/4 pt)
[𝐻 + ] = 10−𝑝𝐻 = 10−10.60 = 2.5 × 10−11 𝑀
(h) Calculate the pOH of sodium hydroxide pH 10.60 𝑝𝐻 + 𝑝𝑂𝐻 = 14.00 𝑝𝑂𝐻 = 14.00 − 𝑝𝐻 = 14.00 − 10.60 = 3.40
Ans & U (½ pt)
Name __________________________________________________ Period ________ Date ______________________
(i) Calculate the [OH-] in sodium hydroxide pH 10.60
Ans & U (½ pt)
Work (1/4)
SF (1/4 pt)
[𝑂𝐻 − ] = 10−𝑝𝑂𝐻 = 10−3.40 = 4.0 × 10−4 𝑀
3. When bromothymol blue is added to H3PO4 what color does it turn? yellow
(½ pt)
4. When bromothymol blue is added to a sodium hydroxide solution, what color does it turn? blue
(½ pt)
