Acids, Bases, and Salts J S 3 Basic Science WEEK 4

TOPIC: Acids, Bases, and Salts
SUBJECT: Basic Science
CLASS: J’S 3
DURATION: 40 minutes
DATE: 

Acids, Bases, and Salts J S 3 Basic Science WEEK 4

LEARNING OBJECTIVES:

By the end of the lesson, students should be able to:

1. Define acids, bases, and salts.
2. Categorize natural and chemical substances as acids or bases using litmus paper and write out their characteristics.
3. Identify the type of acid found in some fruits and food substances.
4. Identify household substances that contain acids, bases, and salts.
5. Prepare a simple salt by different methods.

KEY VOCABULARY WORDS:

• Acid: A substance that tastes sour, turns blue litmus paper red, and reacts with metals to form hydrogen gas.
• Base: A substance that tastes bitter, feels slippery, and turns red litmus paper blue.
• Salt: A compound formed when an acid reacts with a base.
• Litmus Paper: A pH indicator used to test whether a solution is acidic or basic.

CONTENT DETAILS:

1. Definition of Acids, Bases, and Salts:

• Acids: Substances that release hydrogen ions (H⁺) in solution. Examples: lemon juice, vinegar, hydrochloric acid (HCl).
• Bases: Substances that release hydroxide ions (OH⁻) in solution. Examples: baking soda, soap, sodium hydroxide (NaOH).
• Salts: Compounds formed from the neutralization reaction between an acid and a base. Example: table salt (sodium chloride – NaCl).

2. Categorizing Substances Using Litmus Paper:

• Acids turn blue litmus paper red.
• Bases turn red litmus paper blue.

Experiment:

• Use litmus paper to test substances like lemon juice, vinegar, baking soda, and soap to see if they are acidic or basic.

3. Types of Acids Found in Fruits and Food:

• Citric Acid: Found in citrus fruits such as oranges, lemons, and limes.
• Tartaric Acid: Found in grapes and bananas.
• Lactic Acid: Found in sour milk and yogurt.

4. Household Substances Containing Acids, Bases, and Salts:

• Acids: Vinegar, lemon juice, soda drinks.
• Bases: Baking soda, cleaning detergents, soaps.
• Salts: Table salt (sodium chloride), baking powder.

Prepare a simple salt by different methods.

Preparation of a Simple Salt:

There are different methods for preparing salts, including:

1. Neutralization Method:
   • Materials: Acid (e.g., Hydrochloric Acid, HCl) and Base (e.g., Sodium Hydroxide, NaOH).
   • Procedure:
     • Add a measured amount of hydrochloric acid (HCl) to a beaker.
     • Gradually add sodium hydroxide (NaOH) solution to the acid while stirring.
     • Once neutralization occurs (checked using litmus paper), the mixture contains salt (NaCl) and water.
     • Evaporate the water to obtain the salt crystals.

2. Precipitation Method:
   • Materials: Lead nitrate and sodium chloride solutions.
   • Procedure:
     • Mix lead nitrate solution with sodium chloride solution in a beaker.
     • A white precipitate (lead chloride) forms as the salt.
     • Filter the mixture to obtain the solid salt.
     • Dry the salt.

STRATEGIES AND ACTIVITIES:

1. Introduction: Briefly introduce acids, bases, and salts, explaining their definitions and general properties.
2. Group Activity: Divide the class into groups and provide litmus paper and household substances. Students will test the substances and record whether they are acidic or basic.
3. Discussion: After the experiment, discuss which substances were acids, bases, or salts, and their importance in daily life.

ACIDS, BASES, AND SALTS: WEEK 1

WRAP UP & ASSESSMENT:

• Wrap-up: Summarize the lesson by reviewing the definitions of acids, bases, and salts, and their characteristics.
• Assessment:
  1. Define acids, bases, and salts.
  2. Mention the acid found in oranges and vinegar.
  3. List two household substances that contain a base and a salt.

ASSIGNMENT:

1. Identify three more substances at home and determine if they are acidic, basic, or neutral.
2. Write the chemical name of the salt found in table salt and baking soda.

HOD/VP’S COMMENT & ENDORSEMENT:

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