Acids, Bases, and Salts: Fun Experiments at Home

Simple, safe experiments to help Class 7 students understand acids, bases, and salts.

Introduction

Acids and bases are important in our daily life — from the foods we eat to the cleaning products we use. When an acid reacts with a base, they can form a salt and water. These experiments use common household items to show how acids and bases behave. Always follow the safety tips.

Safety first: Ask an adult for permission and help. Wear gloves and eye protection if possible. Do not taste chemicals. If anything spills on skin or eyes, wash immediately with plenty of water.

Materials You Will Need

• White vinegar (acetic acid)
• Baking soda (sodium bicarbonate) — a base
• Lemon or lime (citric acid)
• Household soap or detergent
• Red cabbage (for natural indicator) or store-bought pH strips
• Clear glasses or small transparent containers
• Spoons, measuring spoons, and a tray to avoid mess
• Optional: milk of magnesia or antacid tablets (with adult supervision)

Experiment 1: Vinegar + Baking Soda (Fizzing Chemical Change)

Materials: vinegar, baking soda, small cup

1. Put 2–3 tablespoons of vinegar in a cup.
2. Add a small spoonful of baking soda and watch the fizzing.
3. Try adding more baking soda or more vinegar to see how the reaction changes.

What happens? Vinegar (an acid) reacts with baking soda (a base) to make carbon dioxide gas — that is the fizz. This shows an acid-base reaction.

Experiment 2: Make an Acid–Base Indicator with Red Cabbage

Materials: red cabbage, hot water, strainer, small cups, vinegar, baking soda solution, lemon

1. Chop some red cabbage leaves and put them in a bowl.
2. Pour hot (not boiling) water over the cabbage and let it sit 10–15 minutes.
3. Strain the liquid — this purple liquid is a natural pH indicator.
4. Pour the indicator into small cups. Add a little vinegar to one cup (it should turn pink/red).
5. Add baking soda solution to another cup (it should turn green/blue).
6. Try lemon juice, soap solution, or other liquids and watch color changes.

What happens? The cabbage indicator changes color depending on whether the liquid is acidic or basic. This helps us test pH without strips.

Experiment 3: Neutralizing Acids (Make a Salt and Water)

Materials: vinegar, baking soda, spoon, cup

1. Measure 2 tablespoons of vinegar in a cup.
2. Slowly add baking soda until the reaction stops fizzing.
3. Let the liquid sit so foam goes down; this zone contains the dissolved salt (sodium acetate).

What happens? The acid and base neutralize each other and form a salt dissolved in water. This is called neutralization.

Extra Ideas and Variations

• Use pH strips to measure the exact pH before and after mixing.
• Test which foods are acidic or basic (orange juice, milk, baking soda solution).
• Try making a colorful pH chart using the cabbage indicator to compare common liquids.

Simple Explanation for Class 7 Students

- Acid: A substance that tastes sour and turns blue litmus paper red (example: vinegar, lemon).
- Base: A substance that tastes bitter and feels slippery and turns red litmus paper blue (example: baking soda, soap).
- Salt: What remains after an acid and a base react (example: table salt is formed from acid + base in other reactions).

Important Safety Reminders

• Always do experiments with an adult present.
• Do not mix unknown household chemicals — stick to the listed materials.
• Dispose of mixtures by diluting with water and pouring down the sink (if safe), or follow adult guidance.

Conclusion

These simple experiments make learning acids, bases, and salts fun and memorable. They show real chemical reactions and help you observe changes in color, gas formation, and neutralization. Try them at home, write down observations, and ask: "Why did the color change?" or "How strong was the fizz?" — and you'll be thinking like a young scientist!

Frequently Asked Questions (FAQ)

Q: Can I taste the solutions to check acidity?

A: No — never taste chemicals. Use indicators (cabbage or pH strips) and ask an adult if unsure.

Q: Can I do these experiments in my classroom?

A: Yes — they are classroom friendly. Make sure to have a tray, paper towels, and adult supervision.

Written for Class 7 science learners — try the experiments, stay safe, and have fun exploring!