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Science Quiz - Class 10 Science Chemical Substances

Question 1/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

यदि किसी विलयन का पीएच मान तीन से बढ़कर छह हो जाए, तो उसकी अम्लीयता में क्या परिवर्तन होगा?

If the pH of a solution increases from 3 to 6, what happens to its acidity?

Explanation opens after your attempt

Correct Answer

A. अम्लीयता घटेगीAcidity will decrease

Step 1

Concept

Lower pH means higher acidity.

Step 2

Why this answer is correct

When pH increases from 3 to 6, acidity decreases.

Step 3

Exam Tip

Since pH is still below 7, the solution remains acidic.

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Question 2/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

यदि एक विलयन लाल लिटमस को नीला कर देता है और हल्दी को लाल भूरा कर देता है, तो उसका स्वभाव कैसा होगा?

If a solution turns red litmus blue and turmeric reddish brown, what is its nature?

Explanation opens after your attempt

Correct Answer

B. क्षारीयBasic

Step 1

Concept

Turning red litmus blue is a property of bases.

Step 2

Why this answer is correct

Turmeric becoming reddish brown also indicates a basic medium.

Step 3

Exam Tip

When two indicators give the same clue, the identification is stronger.

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Question 3/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

मैग्नीशियम पट्टी को तनु हाइड्रोक्लोरिक अम्ल में डालने पर बने लवण का नाम क्या होगा?

What is the name of the salt formed when a magnesium ribbon is added to dilute hydrochloric acid?

Explanation opens after your attempt

Correct Answer

C. मैग्नीशियम क्लोराइडMagnesium chloride

Step 1

Concept

A metal reacts with an acid to form a salt and hydrogen gas.

Step 2

Why this answer is correct

Magnesium reacts with hydrochloric acid to form magnesium chloride.

Step 3

Exam Tip

The salt name depends on the metal and the acid radical.

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Question 4/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

जस्ता और तनु सल्फ्यूरिक अम्ल की अभिक्रिया में कौन सा लवण बनता है?

Which salt is formed when zinc reacts with dilute sulphuric acid?

Explanation opens after your attempt

Correct Answer

D. जिंक सल्फेटZinc sulphate

Step 1

Concept

Zinc is a reactive metal and can react with acids.

Step 2

Why this answer is correct

With sulphuric acid, it forms zinc sulphate and hydrogen gas.

Step 3

Exam Tip

Changing the acid changes the salt formed.

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Question 5/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

जल में घुले अम्ल में बल्ब चमकता है, पर शुष्क अम्लीय गैस में नहीं। इसका सही कारण क्या है?

A bulb glows in an aqueous acid but not in dry acidic gas. What is the correct reason?

Explanation opens after your attempt

Correct Answer

A. जल की उपस्थिति में चलायमान आयन बनते हैंMobile ions are produced in the presence of water

Step 1

Concept

Electric current needs mobile charged particles.

Step 2

Why this answer is correct

Acids form ions in water, so current can pass.

Step 3

Exam Tip

In dry conditions, ions are not available, so the bulb does not glow.

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Question 6/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

सोडियम कार्बोनेट में तनु हाइड्रोक्लोरिक अम्ल मिलाने पर कौन से उत्पाद बनेंगे?

What products are formed when dilute hydrochloric acid is added to sodium carbonate?

Explanation opens after your attempt

Correct Answer

B. सोडियम क्लोराइड, जल और कार्बन डाइऑक्साइडSodium chloride, water and carbon dioxide

Step 1

Concept

Carbonates react with acids to release carbon dioxide.

Step 2

Why this answer is correct

Sodium carbonate and hydrochloric acid form sodium chloride, water and carbon dioxide.

Step 3

Exam Tip

The gas can be tested with lime water.

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Question 7/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

किस प्रयोग में चूने के पानी का दूधिया होना सबसे उपयोगी पहचान है?

In which experiment is the milky appearance of lime water the most useful test?

Explanation opens after your attempt

Correct Answer

C. कार्बन डाइऑक्साइड गैस की पहचानIdentification of carbon dioxide gas

Step 1

Concept

Carbon dioxide reacts with lime water.

Step 2

Why this answer is correct

Insoluble calcium carbonate is formed, making lime water milky.

Step 3

Exam Tip

This test identifies the gas released from acid-carbonate reactions.

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Question 8/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

अधिक कार्बन डाइऑक्साइड प्रवाहित करने पर दूधिया चूने का पानी फिर साफ क्यों हो सकता है?

Why can milky lime water become clear again when excess carbon dioxide is passed?

Explanation opens after your attempt

Correct Answer

D. क्योंकि घुलनशील कैल्शियम हाइड्रोजन कार्बोनेट बनता हैBecause soluble calcium hydrogen carbonate is formed

Step 1

Concept

Carbon dioxide first forms calcium carbonate, causing milkiness.

Step 2

Why this answer is correct

Excess carbon dioxide can form soluble calcium hydrogen carbonate.

Step 3

Exam Tip

Therefore, the solution may become clear again.

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Question 9/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

अम्ल का तनुकरण करते समय काँच के पात्र की बाहरी सतह गरम महसूस होती है। यह किस प्रकार की प्रक्रिया को दर्शाता है?

During dilution of an acid, the outer surface of the glass container feels hot. What type of process does this show?

Explanation opens after your attempt

Correct Answer

A. ऊष्माक्षेपी प्रक्रियाExothermic process

Step 1

Concept

During dilution, acid dissolves in water.

Step 2

Why this answer is correct

Heat is released, so the container feels hot.

Step 3

Exam Tip

Acid should always be added slowly to water.

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Question 10/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

एक छात्र ने जल को सांद्र अम्ल में डाल दिया। यह खतरनाक क्यों है?

A student added water to concentrated acid. Why is this dangerous?

Explanation opens after your attempt

Correct Answer

B. क्योंकि तीव्र ऊष्मा से अम्ल के छींटे पड़ सकते हैंBecause intense heat may cause acid splashing

Step 1

Concept

Adding water to concentrated acid releases a lot of heat.

Step 2

Why this answer is correct

The mixture may splash and cause burns.

Step 3

Exam Tip

The safe method is to add acid slowly to water.

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Question 11/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

चार विलयनों के पीएच मान दो, छह, सात और बारह हैं। इनमें सबसे अधिक क्षारीय विलयन कौन सा है?

Four solutions have pH values 2, 6, 7 and 12. Which one is the most basic?

Explanation opens after your attempt

Correct Answer

C. पीएच बारह वाला विलयनSolution with pH 12

Step 1

Concept

A pH greater than 7 indicates a basic solution.

Step 2

Why this answer is correct

Among the given values, pH 12 shows the strongest basic nature.

Step 3

Exam Tip

Higher pH means more basic character.

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Question 12/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

चार विलयनों के पीएच मान एक, चार, आठ और तेरह हैं। इनमें सबसे अधिक अम्लीय विलयन कौन सा है?

Four solutions have pH values 1, 4, 8 and 13. Which one is the most acidic?

Explanation opens after your attempt

Correct Answer

D. पीएच एक वाला विलयनSolution with pH 1

Step 1

Concept

Lower pH indicates higher acidity.

Step 2

Why this answer is correct

Among the given values, pH 1 is the lowest, so it is the most acidic.

Step 3

Exam Tip

Compare pH values carefully in such questions.

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Question 13/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

दूध के खट्टा होने पर उसका पीएच मान किस दिशा में बदलता है?

When milk turns sour, in which direction does its pH change?

Explanation opens after your attempt

Correct Answer

A. पीएच घटता हैpH decreases

Step 1

Concept

When milk turns sour, acidic substances increase.

Step 2

Why this answer is correct

More acidity lowers the pH value.

Step 3

Exam Tip

Connect sour taste with acidic nature for exams.

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Question 14/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

टमाटर के रस, साबुन के विलयन, शुद्ध जल और बेकिंग सोडा विलयन में उदासीन पदार्थ कौन सा होगा?

Among tomato juice, soap solution, pure water and baking soda solution, which substance will be neutral?

Explanation opens after your attempt

Correct Answer

B. शुद्ध जलPure water

Step 1

Concept

A neutral substance has a pH of about 7.

Step 2

Why this answer is correct

Pure water is generally considered neutral.

Step 3

Exam Tip

Tomato juice is acidic, while soap and baking soda solutions are basic.

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Question 15/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

मधुमक्खी के डंक में अम्लीय पदार्थ होता है। उसके दर्द को कम करने के लिए कौन सा पदार्थ उपयुक्त होगा?

A bee sting contains an acidic substance. Which substance is suitable to reduce its pain?

Explanation opens after your attempt

Correct Answer

C. सोडियम हाइड्रोजन कार्बोनेट का विलयनSodium hydrogen carbonate solution

Step 1

Concept

A basic substance can reduce the effect of an acidic sting.

Step 2

Why this answer is correct

Sodium hydrogen carbonate is mildly basic and neutralises the acid.

Step 3

Exam Tip

This is a daily-life example of neutralisation.

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Question 16/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

बिच्छू बूटी के डंक में अम्लीय प्रभाव को कम करने के लिए किस प्रकार का पदार्थ उपयोगी होगा?

Which type of substance is useful to reduce the acidic effect of a nettle sting?

Explanation opens after your attempt

Correct Answer

D. हल्का क्षारMild base

Step 1

Concept

Nettle stings can cause irritation due to acidic substances.

Step 2

Why this answer is correct

A mild base can neutralise the acid.

Step 3

Exam Tip

An acidic effect is treated with a suitable base, not another acid.

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Question 17/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

किस स्थिति में पौधों की जड़ों को मिट्टी से पोषक तत्व लेने में कठिनाई हो सकती है?

In which condition may plant roots face difficulty in absorbing nutrients from soil?

Explanation opens after your attempt

Correct Answer

A. मिट्टी का पीएच बहुत अधिक अम्लीय या बहुत अधिक क्षारीय होSoil pH is highly acidic or highly basic

Step 1

Concept

Plants need a suitable soil pH for proper growth.

Step 2

Why this answer is correct

Highly acidic or highly basic soil can affect nutrient absorption.

Step 3

Exam Tip

This is why farmers treat soil when needed.

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Question 18/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

यदि खेत की मिट्टी बहुत अधिक अम्लीय है, तो उसमें चूना मिलाने से क्या होगा?

If field soil is highly acidic, what happens when lime is added to it?

Explanation opens after your attempt

Correct Answer

B. मिट्टी की अम्लीयता कम होगीSoil acidity decreases

Step 1

Concept

Lime is basic in nature.

Step 2

Why this answer is correct

It reduces the acidity of acidic soil.

Step 3

Exam Tip

This soil treatment is based on neutralisation.

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Question 19/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

दाँतों की सुरक्षा के लिए मंजन सामान्यतः हल्का क्षारीय क्यों बनाया जाता है?

Why is toothpaste generally made mildly basic for tooth protection?

Explanation opens after your attempt

Correct Answer

A. ताकि मुँह में बने अम्ल को निष्क्रिय कर सकेTo neutralise acid formed in the mouth

Step 1

Concept

Bacteria can produce acids after eating.

Step 2

Why this answer is correct

These acids can damage tooth enamel.

Step 3

Exam Tip

Mildly basic toothpaste neutralises the acid and helps protect teeth.

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Question 20/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

पेट में अधिक अम्ल बनने पर मैग्नीशियम हाइड्रॉक्साइड जैसी औषधि कैसे सहायता करती है?

How does a medicine like magnesium hydroxide help when excess acid is produced in the stomach?

Explanation opens after your attempt

Correct Answer

B. यह अतिरिक्त अम्ल को निष्क्रिय करती हैIt neutralises excess acid

Step 1

Concept

Magnesium hydroxide is basic in nature.

Step 2

Why this answer is correct

It reacts with excess stomach acid and neutralises it.

Step 3

Exam Tip

Such medicines are called antacids.

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Question 21/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

सोडियम क्लोराइड का जलीय विलयन किस औद्योगिक प्रक्रिया का प्रारंभिक पदार्थ है?

Aqueous sodium chloride solution is the starting material for which industrial process?

Explanation opens after your attempt

Correct Answer

B. क्लोर क्षार प्रक्रियाChlor-alkali process

Step 1

Concept

Aqueous sodium chloride solution is called brine.

Step 2

Why this answer is correct

Its electrolysis gives chlorine, hydrogen and sodium hydroxide.

Step 3

Exam Tip

This is known as the chlor-alkali process.

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Question 22/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

क्लोर क्षार प्रक्रिया के बाद विलयन में कौन सा क्षार बचता है?

Which base remains in the solution after the chlor-alkali process?

Explanation opens after your attempt

Correct Answer

C. सोडियम हाइड्रॉक्साइडSodium hydroxide

Step 1

Concept

The chlor-alkali process is electrolysis of brine.

Step 2

Why this answer is correct

Chlorine and hydrogen gases are formed, and sodium hydroxide remains in solution.

Step 3

Exam Tip

The word alkali in the name refers to sodium hydroxide.

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Question 23/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

क्लोर क्षार प्रक्रिया में प्राप्त क्लोरीन का एक प्रमुख उपयोग क्या है?

What is one major use of chlorine obtained in the chlor-alkali process?

Explanation opens after your attempt

Correct Answer

C. जल को कीटाणुरहित करनाDisinfecting water

Step 1

Concept

Chlorine has disinfecting properties.

Step 2

Why this answer is correct

Therefore, it is used to disinfect water.

Step 3

Exam Tip

Its related product, bleaching powder, is also useful in water treatment.

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Question 24/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

क्लोर क्षार प्रक्रिया में प्राप्त हाइड्रोजन का एक उपयोग किसमें किया जा सकता है?

One use of hydrogen obtained in the chlor-alkali process is in which of the following?

Explanation opens after your attempt

Correct Answer

A. वनस्पति तेलों के हाइड्रोजनीकरण मेंHydrogenation of vegetable oils

Step 1

Concept

Hydrogen gas is also obtained in the chlor-alkali process.

Step 2

Why this answer is correct

Hydrogen can be used in the hydrogenation of vegetable oils.

Step 3

Exam Tip

Remember the different uses of each industrial product.

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Question 25/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

सोडियम हाइड्रॉक्साइड का उपयोग निम्न में से किस उद्योग में किया जाता है?

Sodium hydroxide is used in which of the following industries?

Explanation opens after your attempt

Correct Answer

A. साबुन और कागज उद्योगSoap and paper industry

Step 1

Concept

Sodium hydroxide is an important industrial base.

Step 2

Why this answer is correct

It is used in making soap, paper and many chemical products.

Step 3

Exam Tip

Uses of chemicals made from common salt are often asked in exams.

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Question 26/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

विरंजक चूर्ण की तैयारी में सूखे बुझा हुए चूने पर कौन सी गैस प्रवाहित की जाती है?

Which gas is passed over dry slaked lime in the preparation of bleaching powder?

Explanation opens after your attempt

Correct Answer

B. क्लोरीनChlorine

Step 1

Concept

Bleaching powder is a useful chlorine-based substance.

Step 2

Why this answer is correct

It is prepared by passing chlorine over dry slaked lime.

Step 3

Exam Tip

Link its preparation with its uses for easier revision.

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Question 27/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

विरंजक चूर्ण को रंगीन पदार्थों का रंग हटाने में क्यों उपयोग किया जाता है?

Why is bleaching powder used to remove colour from coloured substances?

Explanation opens after your attempt

Correct Answer

C. क्योंकि इसमें विरंजन गुण होता हैBecause it has bleaching property

Step 1

Concept

Bleaching powder has the ability to remove colour.

Step 2

Why this answer is correct

Because of this property, it is used in textile and paper industries.

Step 3

Exam Tip

Its name itself indicates its main use.

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Question 28/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

बेकिंग सोडा को गरम करने पर कौन सा मुख्य गैसीय उत्पाद बनता है?

Which main gaseous product is formed when baking soda is heated?

Explanation opens after your attempt

Correct Answer

D. कार्बन डाइऑक्साइडCarbon dioxide

Step 1

Concept

Baking soda decomposes on heating.

Step 2

Why this answer is correct

It releases carbon dioxide gas.

Step 3

Exam Tip

This gas helps food items rise and become soft.

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Question 29/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

बेकिंग सोडा और बेकिंग पाउडर में मुख्य अंतर क्या है?

What is the main difference between baking soda and baking powder?

Explanation opens after your attempt

Correct Answer

B. बेकिंग पाउडर में हल्का खाद्य अम्ल और बेकिंग सोडा दोनों होते हैंBaking powder contains baking soda and a mild edible acid

Step 1

Concept

Baking soda is sodium hydrogen carbonate.

Step 2

Why this answer is correct

Baking powder contains baking soda along with a mild edible acid.

Step 3

Exam Tip

This makes baking powder more suitable for food preparation.

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Question 30/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

केवल बेकिंग सोडा का अधिक उपयोग केक में कड़वा स्वाद क्यों दे सकता है?

Why can excess use of only baking soda give a bitter taste to cake?

Explanation opens after your attempt

Correct Answer

A. क्योंकि उससे क्षारीय पदार्थ बन सकता हैBecause a basic substance may be formed

Step 1

Concept

Baking soda can form a basic substance on heating.

Step 2

Why this answer is correct

This basic substance can give a bitter taste.

Step 3

Exam Tip

The edible acid in baking powder reduces this effect.

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Question 31/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

वाशिंग सोडा का सूत्र सोडियम कार्बोनेट दशजल को दर्शाता है। दशजल शब्द किस बात को बताता है?

The formula of washing soda shows sodium carbonate decahydrate. What does the word decahydrate indicate?

Explanation opens after your attempt

Correct Answer

A. क्रिस्टल में जल के दस अणुTen water molecules in the crystal

Step 1

Concept

Decahydrate means ten molecules of water.

Step 2

Why this answer is correct

Washing soda contains sodium carbonate with water of crystallisation.

Step 3

Exam Tip

Such numbers in hydrated salts are important for exams.

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Question 32/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

कठोर जल में वाशिंग सोडा मिलाने से धुलाई में सहायता क्यों मिलती है?

Why does adding washing soda to hard water help in washing?

Explanation opens after your attempt

Correct Answer

B. यह कैल्शियम और मैग्नीशियम आयनों को हटाने में सहायता करता हैIt helps remove calcium and magnesium ions

Step 1

Concept

Hard water contains calcium and magnesium salts.

Step 2

Why this answer is correct

Washing soda helps remove these ions and softens water.

Step 3

Exam Tip

Soap forms better lather in soft water.

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Question 33/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

नीले कॉपर सल्फेट में जल मिलाने पर नीला रंग वापस क्यों आ जाता है?

Why does the blue colour return when water is added to white copper sulphate?

Explanation opens after your attempt

Correct Answer

C. क्योंकि क्रिस्टलीय जल फिर जुड़ जाता हैBecause water of crystallisation is regained

Step 1

Concept

White copper sulphate lacks water of crystallisation.

Step 2

Why this answer is correct

When water is added, it regains water of crystallisation and the blue colour returns.

Step 3

Exam Tip

This is a good experimental proof of water of crystallisation.

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Question 34/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

कौन सा कथन क्रिस्टलीय जल के बारे में सही है?

Which statement about water of crystallisation is correct?

Explanation opens after your attempt

Correct Answer

B. यह लवण क्रिस्टल में निश्चित अनुपात में उपस्थित जल होता हैIt is water present in a fixed ratio in salt crystals

Step 1

Concept

In some salts, water is attached in a fixed ratio within crystals.

Step 2

Why this answer is correct

This water is called water of crystallisation.

Step 3

Exam Tip

It can affect the colour and shape of crystals.

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Question 35/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

जिप्सम को लगभग तीन सौ तिहत्तर केल्विन पर गरम करने से कौन सा पदार्थ बनता है?

Which substance is formed when gypsum is heated at about 373 K?

Explanation opens after your attempt

Correct Answer

C. प्लास्टर ऑफ पेरिसPlaster of Paris

Step 1

Concept

Gypsum is a hydrated salt of calcium sulphate.

Step 2

Why this answer is correct

On controlled heating, it loses some water of crystallisation and forms plaster of Paris.

Step 3

Exam Tip

Temperature control is important in this preparation.

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Question 36/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

प्लास्टर ऑफ पेरिस को नमी से बचाकर क्यों रखा जाता है?

Why is plaster of Paris stored away from moisture?

Explanation opens after your attempt

Correct Answer

D. क्योंकि नमी पाकर यह धीरे-धीरे जम सकता हैBecause it can gradually set on absorbing moisture

Step 1

Concept

Plaster of Paris reacts with water and becomes hard.

Step 2

Why this answer is correct

If it absorbs moisture, it may set before use.

Step 3

Exam Tip

Therefore, it is stored in a dry place in a closed container.

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Question 37/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

लवण का पीएच किस बात पर निर्भर कर सकता है?

On what can the pH of a salt depend?

Explanation opens after your attempt

Correct Answer

C. जिस अम्ल और क्षार से वह बना है उनकी प्रकृति परOn the nature of the acid and base from which it is formed

Step 1

Concept

Not every salt solution is neutral.

Step 2

Why this answer is correct

The nature of a salt can depend on the acid and base from which it is formed.

Step 3

Exam Tip

Understand combinations of strong and weak acids and bases separately.

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Question 38/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

सोडियम क्लोराइड का जलीय विलयन लगभग उदासीन क्यों होता है?

Why is an aqueous solution of sodium chloride nearly neutral?

Explanation opens after your attempt

Correct Answer

A. क्योंकि यह प्रबल अम्ल और प्रबल क्षार से बना लवण हैBecause it is a salt of a strong acid and a strong base

Step 1

Concept

Sodium chloride is formed from hydrochloric acid and sodium hydroxide.

Step 2

Why this answer is correct

Both are strong, so its solution is nearly neutral.

Step 3

Exam Tip

Such salts usually have pH close to 7.

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Question 39/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

अमोनियम क्लोराइड का जलीय विलयन सामान्यतः कैसा होता है?

What is the usual nature of an aqueous solution of ammonium chloride?

Explanation opens after your attempt

Correct Answer

C. अम्लीयAcidic

Step 1

Concept

Ammonium chloride is considered a salt of a strong acid and a weak base.

Step 2

Why this answer is correct

Its aqueous solution shows acidic nature.

Step 3

Exam Tip

Relate the nature of salts to their parent acid and base.

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Question 40/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

सोडियम कार्बोनेट का जलीय विलयन सामान्यतः किस प्रकृति का होता है?

What is the usual nature of an aqueous solution of sodium carbonate?

Explanation opens after your attempt

Correct Answer

C. क्षारीयBasic

Step 1

Concept

Sodium carbonate is a salt of a weak acid and a strong base.

Step 2

Why this answer is correct

Its aqueous solution is basic in nature.

Step 3

Exam Tip

The basic nature of washing soda is related to its uses.

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Question 41/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

अधातु ऑक्साइड को अम्लीय ऑक्साइड क्यों कहा जाता है?

Why are non-metal oxides called acidic oxides?

Explanation opens after your attempt

Correct Answer

A. क्योंकि वे जल में मिलकर अम्लीय विलयन बना सकते हैंBecause they can form acidic solutions with water

Step 1

Concept

Many non-metal oxides react with water to form acids.

Step 2

Why this answer is correct

Therefore, they are called acidic oxides.

Step 3

Exam Tip

Remember examples like carbon dioxide and sulphur dioxide.

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Question 42/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

धातु ऑक्साइड अम्लों से अभिक्रिया करके लवण और जल बनाते हैं। इससे उनका कौन सा स्वभाव सिद्ध होता है?

Metal oxides react with acids to form salt and water. What nature does this prove?

Explanation opens after your attempt

Correct Answer

B. क्षारीय स्वभावBasic nature

Step 1

Concept

A base reacts with an acid to form salt and water.

Step 2

Why this answer is correct

Metal oxides show the same behaviour with acids.

Step 3

Exam Tip

Therefore, most metal oxides are called basic oxides.

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Question 43/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

अम्ल और क्षार की अभिक्रिया में यदि कोई सूचक रंग बदलना बंद कर दे, तो यह किस स्थिति का संकेत हो सकता है?

In an acid-base reaction, if an indicator stops changing colour, what condition may it indicate?

Explanation opens after your attempt

Correct Answer

C. उदासीनीकरण के पास की स्थितिA condition near neutralisation

Step 1

Concept

An indicator shows whether a solution is acidic or basic.

Step 2

Why this answer is correct

When acid and base are mixed in suitable amounts, the solution can approach neutralisation.

Step 3

Exam Tip

In titration-like experiments, a colour change endpoint is important.

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Question 44/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

घ्राण सूचक किस आधार पर अम्ल और क्षार की पहचान में सहायता करते हैं?

On what basis do olfactory indicators help identify acids and bases?

Explanation opens after your attempt

Correct Answer

B. गंध में परिवर्तन सेBy change in smell

Step 1

Concept

Olfactory indicators are substances whose smell can change in acidic or basic media.

Step 2

Why this answer is correct

Onion, clove and vanilla are examples.

Step 3

Exam Tip

Indicators can give clues by smell, not only by colour.

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Question 45/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

प्याज का रस किस प्रकार के सूचक का उदाहरण है?

Onion juice is an example of which type of indicator?

Explanation opens after your attempt

Correct Answer

A. घ्राण सूचकOlfactory indicator

Step 1

Concept

The smell of onion can behave differently in acidic and basic media.

Step 2

Why this answer is correct

Therefore, onion juice is an olfactory indicator.

Step 3

Exam Tip

Identify olfactory indicators by smell change.

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Question 46/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

यदि किसी विलयन में फिनॉल्फ्थेलीन रंगहीन रहती है, तो कौन सा निष्कर्ष सबसे सावधानीपूर्वक माना जाएगा?

If phenolphthalein remains colourless in a solution, which conclusion is the most careful one?

Explanation opens after your attempt

Correct Answer

B. विलयन अम्लीय या उदासीन हो सकता हैThe solution may be acidic or neutral

Step 1

Concept

Phenolphthalein turns pink in a basic solution.

Step 2

Why this answer is correct

It can remain colourless in acidic or neutral solutions.

Step 3

Exam Tip

Be careful when drawing conclusions from only one indicator.

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Question 47/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

मिथाइल ऑरेंज क्षारीय विलयन में सामान्यतः कौन सा रंग दिखाता है?

What colour does methyl orange generally show in a basic solution?

Explanation opens after your attempt

Correct Answer

C. पीलाYellow

Step 1

Concept

Methyl orange gives different colours in acidic and basic solutions.

Step 2

Why this answer is correct

It is red in acidic solution and yellow in basic solution.

Step 3

Exam Tip

Learn indicator colour changes in pairs.

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Question 48/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

एक विलयन नीले लिटमस को लाल कर देता है और धातु कार्बोनेट से गैस निकालता है। वह विलयन किस प्रकार का होगा?

A solution turns blue litmus red and releases gas with a metal carbonate. What type of solution is it?

Explanation opens after your attempt

Correct Answer

D. अम्लीयAcidic

Step 1

Concept

Turning blue litmus red indicates acidic nature.

Step 2

Why this answer is correct

Acids react with metal carbonates to release carbon dioxide gas.

Step 3

Exam Tip

Both observations confirm acidic nature.

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Question 49/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

यदि किसी अम्ल की थोड़ी मात्रा जल में मिलाई जाए, तो विलयन में किस आयन की मात्रा बढ़ती है?

When a small amount of acid is mixed with water, the amount of which ion increases in the solution?

Explanation opens after your attempt

Correct Answer

B. हाइड्रोजन आयनHydrogen ion

Step 1

Concept

Acids give hydrogen ions in aqueous solution.

Step 2

Why this answer is correct

This is why the solution shows acidic character.

Step 3

Exam Tip

For bases, focus on hydroxide ions.

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Question 50/50 Medium Science Chemical Substances – Nature and Behaviour Acids, Bases, and Salts Class 10 Level 8

यदि किसी क्षार की थोड़ी मात्रा जल में घोली जाए, तो विलयन का पीएच किस दिशा में जाएगा?

If a small amount of base is dissolved in water, in which direction will the pH of the solution move?

Explanation opens after your attempt

Correct Answer

C. सात से अधिक की ओरTowards above 7

Step 1

Concept

Bases produce hydroxide ions in water.

Step 2

Why this answer is correct

A basic solution has pH greater than 7.

Step 3

Exam Tip

Remember the separate directions for acids and bases on the pH scale.

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Class 10 Science - Chemical Substances – Nature and Behaviour - Acids, Bases, and Salts Medium Quiz

यदि किसी विलयन का पीएच मान तीन से बढ़कर छह हो जाए, तो उसकी अम्लीयता में क्या परिवर्तन होगा?

Concept

Why this answer is correct

Exam Tip

यदि एक विलयन लाल लिटमस को नीला कर देता है और हल्दी को लाल भूरा कर देता है, तो उसका स्वभाव कैसा होगा?

Concept

Why this answer is correct

Exam Tip

मैग्नीशियम पट्टी को तनु हाइड्रोक्लोरिक अम्ल में डालने पर बने लवण का नाम क्या होगा?

Concept

Why this answer is correct

Exam Tip

जस्ता और तनु सल्फ्यूरिक अम्ल की अभिक्रिया में कौन सा लवण बनता है?

Concept

Why this answer is correct

Exam Tip

जल में घुले अम्ल में बल्ब चमकता है, पर शुष्क अम्लीय गैस में नहीं। इसका सही कारण क्या है?

Concept

Why this answer is correct

Exam Tip

सोडियम कार्बोनेट में तनु हाइड्रोक्लोरिक अम्ल मिलाने पर कौन से उत्पाद बनेंगे?

Concept

Why this answer is correct

Exam Tip

किस प्रयोग में चूने के पानी का दूधिया होना सबसे उपयोगी पहचान है?

Concept

Why this answer is correct

Exam Tip

अधिक कार्बन डाइऑक्साइड प्रवाहित करने पर दूधिया चूने का पानी फिर साफ क्यों हो सकता है?

Concept

Why this answer is correct

Exam Tip

अम्ल का तनुकरण करते समय काँच के पात्र की बाहरी सतह गरम महसूस होती है। यह किस प्रकार की प्रक्रिया को दर्शाता है?

Concept

Why this answer is correct

Exam Tip

एक छात्र ने जल को सांद्र अम्ल में डाल दिया। यह खतरनाक क्यों है?

Concept

Why this answer is correct

Exam Tip

चार विलयनों के पीएच मान दो, छह, सात और बारह हैं। इनमें सबसे अधिक क्षारीय विलयन कौन सा है?

Concept

Why this answer is correct

Exam Tip

चार विलयनों के पीएच मान एक, चार, आठ और तेरह हैं। इनमें सबसे अधिक अम्लीय विलयन कौन सा है?

Concept

Why this answer is correct

Exam Tip

दूध के खट्टा होने पर उसका पीएच मान किस दिशा में बदलता है?

Concept

Why this answer is correct

Exam Tip

टमाटर के रस, साबुन के विलयन, शुद्ध जल और बेकिंग सोडा विलयन में उदासीन पदार्थ कौन सा होगा?

Concept

Why this answer is correct

Exam Tip

मधुमक्खी के डंक में अम्लीय पदार्थ होता है। उसके दर्द को कम करने के लिए कौन सा पदार्थ उपयुक्त होगा?

Concept

Why this answer is correct

Exam Tip

बिच्छू बूटी के डंक में अम्लीय प्रभाव को कम करने के लिए किस प्रकार का पदार्थ उपयोगी होगा?

Concept

Why this answer is correct

Exam Tip

किस स्थिति में पौधों की जड़ों को मिट्टी से पोषक तत्व लेने में कठिनाई हो सकती है?

Concept

Why this answer is correct

Exam Tip

यदि खेत की मिट्टी बहुत अधिक अम्लीय है, तो उसमें चूना मिलाने से क्या होगा?

Concept

Why this answer is correct

Exam Tip

दाँतों की सुरक्षा के लिए मंजन सामान्यतः हल्का क्षारीय क्यों बनाया जाता है?

Concept

Why this answer is correct

Exam Tip

पेट में अधिक अम्ल बनने पर मैग्नीशियम हाइड्रॉक्साइड जैसी औषधि कैसे सहायता करती है?

Concept

Why this answer is correct