Conjugate Acid–Base Pairs & Buffer Worksheet
Name: ______________________
Date: ______________
Part A: Identify the Conjugate Pair
For each reaction below, identify the acid, base, conjugate acid, and conjugate base.
1. H₂CO₃ ⇌ HCO₃⁻ + H⁺
2. NH₃ + H⁺ ⇌ NH₄⁺
3. CH₃COOH ⇌ CH₃COO⁻ + H⁺
4. H₂O + NH₃ ⇌ OH⁻ + NH₄⁺
Part B: How to Prepare the Conjugate?
Fill in the blanks to show how conjugates are prepared.
1. CH₃COOH + __________ → CH₃COONa + H₂O
2. NH₃ + __________ → NH₄Cl
3. To make a buffer solution with CH₃COOH, mix it with __________
4. To make a buffer solution with NH₃, mix it with __________
Part C: Identify the Buffer Type
Determine whether the following combinations create an acidic or basic buffer.
Fill in: Acidic / Basic
Components
CH₃COOH + CH₃COONa
NH₃ + NH₄Cl
HCl + NH₃
NaOH + CH₃COOH
Buffer Type?
Answer Key
Part A Answers
1. Acid: H₂CO₃ | Conjugate base: HCO₃⁻
2. Base: NH₃ | Conjugate acid: NH₄⁺
3. Acid: CH₃COOH | Conjugate base: CH₃COO⁻
4. Base: NH₃ | Conjugate acid: NH₄⁺
Part B Answers
1. CH₃COOH + NaOH → CH₃COONa + H₂O
2. NH₃ + HCl → NH₄Cl
3. To make a buffer with CH₃COOH, mix it with CH₃COONa
4. To make a buffer with NH₃, mix it with NH₄Cl
Part C Answers
Components
Buffer Type
CH₃COOH + CH₃COONa
Acidic buffer
NH₃ + NH₄Cl
Basic buffer
HCl + NH₃
Basic buffer
NaOH + CH₃COOH
Acidic buffer