# Lesson Plan: Acid-Base Reactions
## Grade Level: Senior Secondary 2
## Subject: Chemistry
## Duration: 80 minutes
### **Objective:**
- Students will understand the concepts of acids, bases, and their reactions.
- Students will be able to write and balance acid-base chemical equations.
- Students will grasp the practical applications of acid-base reactions in everyday life.
### **Materials Needed:**
- Whiteboard and markers
- Projector and computer for presentation
- Handouts with practice problems
- pH strips
- Solutions of common acids (e.g., hydrochloric acid, acetic acid) and bases (e.g., sodium hydroxide, ammonia)
- Safety goggles and gloves
### **Lesson Outline:**
1. **Introduction (10 minutes)**
- **Hook:** Begin with a simple demonstration: Add a few drops of hydrochloric acid (HCl) to a solution of sodium hydroxide (NaOH) and observe the reaction. Show how the pH changes using pH strips.
- **Discussion**: Briefly recap properties of acids and bases, and introduce the concept of neutralization. Discuss real-life examples (e.g., stomach acid neutralized by antacids).
2. **Direct Instruction (15 minutes)**
- **Presentation**: Use slides to explain:
- Definitions: Acid (proton donor), Base (proton acceptor).
- The Bronsted-Lowry Theory.
- The concept of pH and the pH scale.
- General equation for an acid-base reaction: Acid + Base → Salt + Water.
- Strong vs. weak acids and bases.
3. **Guided Practice (20 minutes)**
- **Balancing Equations**: Go through examples of acid-base reactions on the whiteboard.
- Example 1: HCl + NaOH → NaCl + H₂O
- Example 2: CH₃COOH + NH₃ → CH₃COONH₄
- **Interactive Quiz**: Present some unbalanced reactions for students to balance and identify the salt formed.
4. **Lab Activity (25 minutes)**
- **Experiment**: Students will work in pairs to:
- Test the pH of various household solutions (vinegar, baking soda solution, lemon juice, etc.).
- Conduct a neutralization reaction using citric acid and sodium bicarbonate.
- **Worksheet**: Students will record their observations and answer questions about the reactions they observed (e.g., what evidence indicates a reaction has occurred?).
5. **Closure (5 minutes)**
- **Review Key Points**: Reiterate the importance of acid-base reactions and their practical applications.
- **Q&A**: Open the floor for any questions students may have.
6. **Assessment (5 minutes)**
- **Exit Ticket**: Have students write down one key thing they learned and one question they still have about acid-base reactions.
### **Homework:**
- **Worksheet**: Assign a set of practice problems involving acid-base reactions to reinforce the day’s lesson.
### **Safety Considerations:**
- Ensure students wear safety goggles and gloves during the lab activity.
- Explain the proper handling and disposal of acids and bases.
- Supervise students closely to prevent any accidents.
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By the end of the lesson, students should have a firm understanding of acid-base reactions, how to balance the corresponding equations, and recognize the importance of these reactions in everyday life.