Acid-base reactions and titration (more worked examples)
1. Write the formulas for the conjugate bases of the following acids:
a. HCN
b. HCO3c. CH3COOH
2. Write the formulas for the conjugate acids of the following bases:
a. HCO3b. NH3
c. C2H5O3. Given the following reactions, please answer the following questions:
a. In the reaction :NH3 + H2O  NH4+ + OH-, water is a bronsted-lowry acid to which base?
b. In the complexation reaction, Al3+ (aq) + 6H2O (l)  Al(H2O)63+ (aq), Al3+ is a _________ acid.
4. What is the pH of a buffer solution when 0.60 L of 0.3 M acetic acid is mixed with 0.40 L of 0.2 M
sodium acetate? (use Henderson-Hasselbalch equation) the Ka of acetic acid is 1.8 x 10-5.
5. (same buffer as number 4) What is the pH of the solution when you add 0.03 moles of NaOH in the
buffer?
Answer key:
1. a. CNb. CO32c. CH3COO2. a. H2CO3
b. NH4+
c. C2H5OH
3. a. NH3
b. Lewis
4. pH = 4.38
5. pH = 4.61