1. Unit 4: Acid-Base Theory
Lesson 4: Conjugate Acids and Bases

2. Conjugate Pairs
A conjugate acid-base pair is a pair of chemical species that differ by only a proton.
Think-Pair-Share:
The reaction
NH3 + H2O NH4+ + OH-
has two conjugate pairs. What are they?
5 min

3. Practice:
In each pair, identify the conjugate acid and the conjugate base:
CH3COOH / CH3COO-
HSO4- / SO42-
PH3 / PH4+
5 min

4. Try This! What is the conjugate acid of NH3?
What is the conjugate base of NH3?
What is the conjugate base of CH3CH2COOH?
What is the conjugate acid of CH3CH2NH2?
What is the conjugate base of (CH3)2NH2+?
10 min

5. Brain Break – Spot 7 Differences!

6. Playing Proton Toss
A Bronsted-Lowry acid-base reaction just involves an equilibrium proton transfer!
Thus, every Bronsted-Lowry acid-base reaction involves two conjugate acid-base pairs.
E.g. The reaction between H2S and CO32-...
Model using a ball and two people. – 10 min

7. NOC while watching:
10 min

8. Homework:
Pg. 121 #16-19
5 min