Class 7 Science Acids Bases and Salts Important Questions with Answers

📝 Important Questions & Answers- Class 7 CH-02

🔹 Short Questions (English) Class 7 CH-02

Q1. What is an acid? ( CLASS 7)

👉 A substance that tastes sour and turns blue litmus red.

Q2. What is a base?
👉 A substance that tastes bitter and turns red litmus blue.

Q3. What is neutralization?
👉 Reaction between acid and base to form salt and water.

Q4. Give one use of neutralization.
👉 Antacids reduce stomach acidity.

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🔹 लघु प्रश्न (Hindi)

🔹 लघु प्रश्न (Hindi) Class 7 CH-02

प्र1. अम्ल क्या है?
👉 खट्टा पदार्थ जो नीला लिटमस लाल करता है।

प्र2. क्षार क्या है?
👉 कड़वा पदार्थ जो लाल लिटमस नीला करता है।

प्र3. उदासीनीकरण क्या है?
👉 अम्ल और क्षार की अभिक्रिया जिससे लवण और पानी बनते हैं।

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🔹 🔥 Important Exam Questions

🔹 🔥 Important Exam Questions Class 7 CH-02

• Define acids, bases, and salts
• Explain neutralization with example
• Name 2 indicators and their uses
• Write differences between acids and bases

🧪 Real-Life Examples (English)

🔹 Acids in Daily Life

• Lemon, orange → contain acid (sour taste)
• Vinegar → used in food
• Curd → slightly acidic

👉 That’s why these taste sour

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🔹 Bases in Daily Life

• Soap → slippery
• Toothpaste → basic (protects teeth)
• Baking soda → used in cooking

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🔹 Neutralization in Life

• Stomach acidity → we take antacids (base)
• Bee sting (acidic) → relief with mild base like baking soda
• Wasp sting (basic) → relief with weak acid like vinegar

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🧪 दैनिक जीवन के उदाहरण (Hindi) Class 7 CH-02

🧪 दैनिक जीवन के उदाहरण (Hindi)

🔹 अम्ल (Acids)

• नींबू, संतरा → खट्टा
• सिरका → भोजन में
• दही → हल्का अम्लीय

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🔹 क्षार (Bases)

• साबुन → फिसलन वाला
• टूथपेस्ट → दांतों की सुरक्षा
• बेकिंग सोडा

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🔹 उदासीनीकरण (Neutralization)

• पेट की जलन → एंटासिड
• मधुमक्खी का डंक → बेस से राहत
• ततैया का डंक → अम्ल से राहत

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🔬 Easy Home Experiments (Safe)

🧪 Experiment 1: Litmus Test

🧾 Materials:

• Blue & Red litmus paper
• Lemon juice
• Soap solution

👉 Steps:

1. Put lemon juice on blue litmus
2. Put soap solution on red litmus

✅ Result:

• Lemon → blue to red (Acid)
• Soap → red to blue (Base)

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🧪 प्रयोग 1 (Hindi)

• नींबू → नीला लिटमस लाल
• साबुन → लाल लिटमस नीला

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🧪 Experiment 2: Turmeric Indicator

🧾 Materials:

• Turmeric paste/powder
• Soap solution

👉 Steps:

1. Apply turmeric on paper
2. Add soap solution

✅ Result:

• Turns reddish → shows base

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🧪 प्रयोग 2 (Hindi)

• हल्दी + साबुन → लाल/भूरा रंग
  👉 यह क्षार दर्शाता है

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🧪 Experiment 3: Neutralization Reaction

🧾 Materials:

• Vinegar (acid)
• Baking soda (base)

👉 Steps:

1. Mix both in a bowl

✅ Result:

• Bubbling (gas forms)
• Shows neutralization

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🧪 प्रयोग 3 (Hindi)

• सिरका + बेकिंग सोडा
  👉 झाग बनता है → उदासीनीकरण

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⚠️ Safety Tips

• Don’t taste unknown substances
• Use small quantities
• Wash hands after experiment

🧠 Quick Understanding Trick

• Sour → Acid 🍋
• Slippery → Base 🧼
• Mix → Neutral (Salt + Water)

CONCLUSION

Acids, Bases and Salts play an important role in science as well as daily life. Although acids and bases have different properties, they react together through neutralization to form salt and water. Therefore, understanding this chapter helps students connect science concepts with real-life examples like toothpaste, antacids, vinegar, soap, and baking soda.

Moreover, indicators such as litmus, turmeric, and china rose make it easy to identify acidic and basic substances. The experiments and important questions included in this chapter also help students improve practical knowledge and exam preparation.

By revising these notes regularly, students can easily remember key concepts and score better in examinations. Keep visiting Rising Star Mindset for more Class 7 Science notes, important questions, educational posts, and study materials.