Materials Around Us – Important Questions and Answers
Premium CBSE Class 6 Science revision post based on the chapter Materials Around Us. Includes materials, objects, classification, properties of materials, lustrous and non-lustrous materials, hard and soft materials, transparent, translucent and opaque materials, soluble and insoluble materials, mass, volume, matter, case studies, HOTS questions, diagram-based questions, FAQs, and an interactive quiz.
Short Introduction
Everything around us is made up of one or more materials. A notebook is made of paper, a table may be made of wood, a tumbler may be made of glass, metal or plastic, and a pen may be made of plastic, metal and ink. This chapter teaches students how to observe objects, identify the materials they are made of, classify materials based on their properties, and understand important ideas such as mass, volume and matter.
Chapter Overview
Objects and Materials
Objects are made from materials such as paper, wood, cloth, glass, metal, plastic and clay.
Classification
Classification means arranging objects or materials into groups based on common properties.
Appearance
Materials may be lustrous or non-lustrous depending on whether they have a shiny surface.
Hardness and Softness
Materials that are difficult to compress or scratch are hard, while those that are easy to compress or scratch are soft.
Transparency
Materials can be transparent, translucent or opaque depending on how clearly we can see through them.
Matter
Anything that occupies space and has mass is called matter.
Important Concept Flow
Example: Notebook → Paper, Pen → Plastic + Metal + Ink.
Objects can be classified on the basis of shape, colour, hardness, lustre or material.
Anything that has mass and occupies space is matter.
Some materials dissolve in water, while some do not dissolve.
Important Keywords with Meanings
| Keyword | Meaning |
|---|---|
| Object | A thing that we can see or use, such as a table, pen, tumbler or bottle. |
| Material | Any substance used to create or make an object. |
| Classification | The method of arranging objects or materials into groups based on common properties. |
| Property | A feature or quality of a material, such as hardness, softness, lustre or solubility. |
| Lustrous | Having a shiny surface. Metals usually show lustre. |
| Non-lustrous | Not having a shiny surface, such as paper, wood, rubber and jute. |
| Metal | A material usually having lustre, such as iron, copper, aluminium, zinc and gold. |
| Hard material | A material that is difficult to compress or scratch. |
| Soft material | A material that can be compressed or scratched easily. |
| Transparent | A material through which objects can be seen clearly. |
| Translucent | A material through which objects can be seen, but not clearly. |
| Opaque | A material through which objects cannot be seen at all. |
| Soluble | A material that dissolves completely in water. |
| Insoluble | A material that does not dissolve in water. |
| Mass | The quantity of matter present in an object. |
| Volume | The space occupied by matter. |
| Matter | Anything that occupies space and has mass. |
| Gram | A unit used to measure small masses; symbol is g. |
| Kilogram | SI unit of mass; symbol is kg. |
| Litre | A unit used to measure volume; symbol is L. |
| Millilitre | A smaller unit of volume; symbol is mL. |
| Cubic metre | SI unit of volume; symbol is m3. |
| ORS | Oral Rehydration Solution prepared using sugar, salt and water to treat dehydration. |
| Terracotta | Baked clay used to make pots and other objects. |
Very Short Answer Questions
1. What is a material?
Answer: A material is any substance used to create or make an object.
2. Give two examples of materials.
Answer: Wood and plastic.
3. Give one example of an object made of paper.
Answer: Notebook.
4. Can one object be made of more than one material?
Answer: Yes, a pen may be made of plastic, metal and ink.
5. What is classification?
Answer: Classification is arranging objects or materials into groups based on common properties.
6. Name one property used to classify materials.
Answer: Hardness.
7. What are lustrous materials?
Answer: Materials with a shiny surface are called lustrous materials.
8. Give one example of a lustrous material.
Answer: Copper.
9. What are non-lustrous materials?
Answer: Materials that do not have a shiny surface are called non-lustrous materials.
10. Give one example of a non-lustrous material.
Answer: Wood.
11. What are hard materials?
Answer: Materials that are difficult to compress or scratch are called hard materials.
12. What are soft materials?
Answer: Materials that can be compressed or scratched easily are called soft materials.
13. Give one example of a transparent material.
Answer: Glass.
14. Give one example of a translucent material.
Answer: Frosted glass.
15. Give one example of an opaque material.
Answer: Wood.
16. What are soluble materials?
Answer: Materials that dissolve completely in water are called soluble materials.
17. Give one example of a soluble material.
Answer: Sugar.
18. What are insoluble materials?
Answer: Materials that do not dissolve in water are called insoluble materials.
19. Give one example of an insoluble material.
Answer: Sand.
20. What is mass?
Answer: Mass is the quantity of matter present in an object.
21. What is volume?
Answer: Volume is the space occupied by matter.
22. What is matter?
Answer: Anything that occupies space and has mass is called matter.
23. What is the SI unit of mass?
Answer: Kilogram is the SI unit of mass.
24. What is the SI unit of volume?
Answer: Cubic metre is the SI unit of volume.
Short Answer Questions
1. Why do we classify materials?
Answer: We classify materials to study them easily. Classification helps us observe similarities and differences in properties such as colour, shape, hardness, softness, lustre, transparency and solubility.
2. How can the same object be made from different materials?
Answer: The same object can be made from different materials depending on its use. For example, a tumbler can be made of glass, metal, plastic or clay because all these materials can hold water.
3. How can one material be used to make many objects?
Answer: One material can be used to make many objects because it may have useful properties. For example, wood can be used to make tables, chairs, doors, pencils and shelves.
4. Why is cloth not suitable for making a tumbler?
Answer: Cloth is not suitable for making a tumbler because it cannot hold water properly. Water passes through or soaks into cloth.
5. Why is paper not suitable for making cooking utensils?
Answer: Paper is not suitable because it is soft, weak and can burn easily when heated. Cooking utensils should be hard, strong and heat-resistant.
6. What is lustre? Give examples.
Answer: Lustre is the shiny appearance of a material. Metals such as iron, copper, aluminium, zinc and gold are usually lustrous.
7. Why do some metals look dull after some time?
Answer: Some metals lose their lustre and look dull due to the effect of air and moisture on their surface. Their freshly cut surface may still appear shiny.
8. Are all shiny materials metals?
Answer: No, all shiny materials are not metals. Some objects look shiny because they are polished or coated with plastic, wax or another shiny material.
9. How can we test hardness of materials?
Answer: We can press or scratch materials. Materials that are difficult to compress or scratch are hard, while materials that are easily compressed or scratched are soft.
10. Differentiate between transparent and opaque materials.
Answer: Transparent materials allow us to see clearly through them, such as glass and water. Opaque materials do not allow us to see through them, such as wood and metal.
11. What are translucent materials?
Answer: Translucent materials allow light to pass through them, but objects cannot be seen clearly through them. Examples are butter paper and frosted glass.
12. What happens when sugar and salt are mixed in water?
Answer: Sugar and salt disappear after stirring because they dissolve in water. They are soluble in water.
13. What happens when sand and sawdust are mixed in water?
Answer: Sand and sawdust do not dissolve in water. They remain visible even after stirring and are called insoluble materials.
14. Why is oxygen dissolved in water important?
Answer: Oxygen dissolved in water is important for the survival of aquatic animals and plants.
15. Why are transparent containers commonly used in shops and homes?
Answer: Transparent containers allow us to see the material stored inside clearly without opening the container. This makes storage and identification easy.
Long Answer Questions
1. Explain the difference between objects and materials with examples.
Answer: An object is a thing that we can see or use, while a material is the substance used to make that object. For example, a notebook is an object and paper is the material used to make it. A tumbler is an object and it may be made of glass, metal, plastic or clay. A pen is an object and it can be made of plastic, metal and ink. Thus, objects are made from one or more materials.
2. What is classification? Why is it useful?
Answer: Classification is the method of arranging objects or materials into groups based on common properties. It is useful because:
- It helps us study materials easily.
- It helps us compare similarities and differences.
- It helps us observe patterns in properties.
- It helps us choose suitable materials for making objects.
- It is used in daily life, such as arranging utensils, groceries and medicines.
3. Explain lustrous and non-lustrous materials.
Answer: Materials with shiny surfaces are called lustrous materials. Metals such as iron, copper, zinc, aluminium and gold usually show lustre. Sometimes metals may look dull because of the effect of air and moisture, but their freshly cut surfaces may still shine. Materials that do not have a shiny surface are called non-lustrous materials. Examples include paper, wood, rubber and jute. However, all shiny materials are not metals because polishing or coating can also make a surface look shiny.
4. Explain hard and soft materials with examples.
Answer: Materials that are difficult to compress or scratch are called hard materials. Examples include stone, iron, aluminium and brick. Materials that can be compressed or scratched easily are called soft materials. Examples include sponge, pillow, candle and eraser. Hardness and softness are relative properties. For example, rubber is harder than sponge but softer than iron.
5. Differentiate between transparent, translucent and opaque materials.
| Type of Material | Meaning | Examples |
|---|---|---|
| Transparent | Objects can be seen clearly through them. | Glass, water, air, cellophane paper |
| Translucent | Objects can be seen, but not clearly. | Butter paper, frosted glass |
| Opaque | Objects cannot be seen through them. | Wood, cardboard, metals |
6. Explain soluble and insoluble materials with examples.
Answer: Materials that dissolve completely in water are called soluble materials. Sugar and salt dissolve in water and become invisible after stirring. Materials that do not dissolve in water are called insoluble materials. Sand, chalk powder and sawdust do not disappear in water even after stirring. Some liquids mix completely with water, while some liquids form a separate layer. Some gases, such as oxygen, also dissolve in water and support aquatic life.
7. What is ORS? How can it be prepared at home?
Answer: ORS stands for Oral Rehydration Solution. It is used to treat dehydration caused by diarrhoea or other illnesses. Ready-made ORS packets are available in primary health centres and markets. If ready-made ORS is not available, it can be prepared at home by mixing six teaspoons of sugar and half a teaspoon of common salt in one litre of boiled and cooled water.
8. Explain mass and volume.
Answer: Mass is the quantity of matter present in an object. A heavier object has more mass and a lighter object has less mass. Mass is measured in gram and kilogram. Volume is the space occupied by matter. For example, water in a half-filled tumbler occupies less space than water in a fully-filled tumbler. Volume is measured in litre, millilitre and cubic metre.
9. What is matter? Explain with examples.
Answer: Anything that occupies space and has mass is called matter. Water, sand, pebbles, air, cup, apple and wood are examples of matter because they have mass and occupy space. Materials are types of matter used to make objects. All materials possess mass and volume.
10. Explain how properties of materials decide their use.
Answer: Materials are chosen for making objects according to their properties and purpose. A tumbler should be made of a material that can hold water, such as glass, metal, plastic or clay. A chair should be hard and strong so that it does not bend when someone sits on it. Transparent containers are used for storing things because we can see their contents. Cooking utensils are made from materials that can withstand heat. Thus, properties of materials decide their use.
Case-Study Based Questions
Case Study 1: Choosing a Tumbler
Sheeta wants to make a tumbler. She has paper, cloth, glass, plastic and metal. She wants the tumbler to hold water properly.
Q1. Which materials are suitable for making the tumbler?
Answer: Glass, plastic and metal are suitable.
Q2. Why is cloth not suitable?
Answer: Cloth cannot hold water properly because water can pass through or soak into it.
Q3. What decides the choice of material?
Answer: The properties of the material and the purpose of the object decide the choice.
Case Study 2: Hide and Seek
Ghulan hides behind a wall, Sara hides behind a frosted glass door, and another child watches through a glass window.
Q1. What type of material is the wall?
Answer: The wall is opaque.
Q2. What type of material is frosted glass?
Answer: Frosted glass is translucent.
Q3. What type of material is window glass?
Answer: Window glass is transparent.
Case Study 3: Shikanji
Ghulan’s mother prepares shikanji by mixing sugar, salt and lemon juice in water. Ghulan observes that sugar and salt disappear after stirring.
Q1. Why do sugar and salt disappear?
Answer: They disappear because they dissolve in water.
Q2. What are such materials called?
Answer: They are called soluble materials.
Q3. Name one material that will not dissolve in water.
Answer: Sand.
Case Study 4: Transparent Containers
A shopkeeper stores pulses, rice, spices and sweets in transparent containers.
Q1. Why are transparent containers useful?
Answer: They allow the shopkeeper and customers to see the contents clearly.
Q2. Give one transparent material used for containers.
Answer: Glass or clear plastic.
Q3. Would an opaque container allow the same visibility?
Answer: No, objects cannot be seen through an opaque container.
Case Study 5: Bags on Seats
Madam Vidya asks students to keep their bags on their seats and sit down. Students cannot sit because the bags occupy the space on the seats.
Q1. What property of matter is shown here?
Answer: Matter occupies space.
Q2. Are school bags matter?
Answer: Yes, school bags are matter because they occupy space and have mass.
Q3. Define matter.
Answer: Anything that occupies space and has mass is called matter.
Assertion-Reason Questions
Choose the correct option:
A. Both Assertion and Reason are true and Reason is the correct explanation.
B. Both Assertion and Reason are true but Reason is not the correct explanation.
C. Assertion is true but Reason is false.
D. Assertion is false but Reason is true.
1. Assertion: Objects are made of materials. Reason: Paper, wood, glass, metal and plastic are examples of materials.
Answer: A
2. Assertion: Classification helps us study materials easily. Reason: Classification groups materials based on common properties.
Answer: A
3. Assertion: A tumbler can be made from cloth. Reason: Cloth can hold water without soaking it.
Answer: Both Assertion and Reason are false.
4. Assertion: Metals usually have lustre. Reason: Materials with shiny surfaces are said to be lustrous.
Answer: A
5. Assertion: All shiny materials are metals. Reason: Some materials may look shiny due to polishing or coating.
Answer: D
6. Assertion: Wood is opaque. Reason: We cannot see through wood.
Answer: A
7. Assertion: Frosted glass is translucent. Reason: Objects can be seen through frosted glass, but not clearly.
Answer: A
8. Assertion: Sugar is insoluble in water. Reason: Sugar disappears when stirred in water.
Answer: D
9. Assertion: Matter occupies space and has mass. Reason: Air is not matter because it cannot be seen.
Answer: C
10. Assertion: Volume is the space occupied by matter. Reason: Litre and millilitre are used to measure volume.
Answer: A
Competency-Based and Critical Thinking / HOTS Questions
1. Why can the same object be made from different materials?
Answer: The same object can be made from different materials if those materials have suitable properties for the same purpose. For example, a tumbler can be made of glass, plastic, metal or clay because all can hold water.
2. A material X is shiny but is not a metal. How is this possible?
Answer: The material may have been polished or coated with a shiny layer of plastic, wax or another substance. Therefore, all shiny materials are not metals.
3. Why is a cricket ball not suitable for playing tennis?
Answer: A cricket ball and tennis ball are made of different materials and have different hardness, bounce and purpose. A cricket ball is harder and does not behave like a tennis ball during play.
4. Why is transparent glass preferred for windows?
Answer: Transparent glass allows light to pass through and lets us see clearly outside while still providing a barrier from wind, dust and rain.
5. Why is a wooden door useful for privacy?
Answer: A wooden door is opaque, so people cannot see through it. This provides privacy and safety.
6. Is water always transparent?
Answer: Clean water is transparent. However, if mud, chalk powder or other insoluble materials are mixed with water, it may become cloudy or opaque.
7. Why does sawdust not disappear in water?
Answer: Sawdust is insoluble in water. It does not dissolve even after stirring and remains visible.
8. Is air matter even though we cannot see it?
Answer: Yes, air is matter because it occupies space and has mass, even though it cannot be seen.
9. Why should waste containers be made of suitable materials?
Answer: Waste containers must be chosen according to the type of waste. For food waste, the container should be washable and leak-proof. For broken glass, it should be strong and hard. For wastepaper, it may be lightweight and dry.
10. Plastic brought many changes to human life. Is it a boon or a bane?
Answer: Plastic is useful because it is lightweight, cheap, waterproof and can be shaped easily. But it is harmful when overused because it creates pollution and is difficult to decompose. Therefore, plastic is useful when used responsibly but harmful when misused.
Diagram-Based Questions
Diagram 1: Object and Material Relation
Question: Can one object be made of more than one material?
Answer: Yes, a pen can be made of plastic, metal and ink.
Diagram 2: Classification of Materials
Lustrous
Iron, copper, aluminium
Non-lustrous
Wood, paper, rubber
Hard / Soft
Stone / Sponge
Question: Which property is used to group copper and aluminium together?
Answer: Lustre or shiny appearance.
Diagram 3: Transparent, Translucent and Opaque
Transparent
See clearly
Example: Glass
Translucent
See, but not clearly
Example: Frosted glass
Opaque
Cannot see through
Example: Wood
Question: Which type of material is butter paper?
Answer: Butter paper is translucent.
Diagram 4: Soluble and Insoluble Materials
Soluble in Water
Sugar, salt
Insoluble in Water
Sand, sawdust, chalk powder
Question: What happens when salt is stirred in water?
Answer: Salt dissolves in water.
Diagram 5: Matter Concept
Question: Is air matter?
Answer: Yes, air is matter because it has mass and occupies space.
Quick Revision Box
- Objects are made from materials.
- A material is any substance used to create an object.
- An object may be made of one or more materials.
- One material may be used to make many objects.
- Classification means arranging objects into groups.
- Materials are classified based on properties.
- Lustrous materials have shiny surfaces.
- Metals usually have lustre.
- Non-lustrous materials do not have shiny surfaces.
- Hard materials are difficult to compress or scratch.
- Soft materials are easy to compress or scratch.
- Transparent materials allow clear vision through them.
- Translucent materials allow unclear vision through them.
- Opaque materials do not allow us to see through them.
- Soluble materials dissolve in water.
- Insoluble materials do not dissolve in water.
- Sugar and salt are soluble in water.
- Sand and sawdust are insoluble in water.
- Oxygen dissolved in water helps aquatic life.
- Mass tells the amount of matter in an object.
- Volume is the space occupied by matter.
- Anything that occupies space and has mass is matter.
- Mass is measured in g and kg.
- Volume is measured in L and mL.
Important Exam Tips
Interactive Quiz
Choose the correct answer and click submit.
Frequently Asked Questions
1. What is a material?
A material is any substance used to create or make an object.
2. What is classification?
Classification is arranging objects or materials into groups based on common properties.
3. What are lustrous materials?
Materials with shiny surfaces are called lustrous materials.
4. Are all shiny materials metals?
No, some materials look shiny because of polishing or coating and may not be metals.
5. What is the difference between hard and soft materials?
Hard materials are difficult to compress or scratch, while soft materials are easy to compress or scratch.
6. What is the difference between transparent, translucent and opaque materials?
Transparent materials allow clear vision, translucent materials allow unclear vision and opaque materials do not allow us to see through them.
7. What are soluble materials?
Materials that dissolve completely in water are called soluble materials.
8. What are insoluble materials?
Materials that do not dissolve in water are called insoluble materials.
9. What is mass?
Mass is the quantity of matter present in an object.
10. What is matter?
Anything that occupies space and has mass is called matter.
Final Conclusion
The chapter Materials Around Us teaches that all objects around us are made from materials. Materials are chosen according to their properties and the purpose for which objects are used. By studying lustre, hardness, transparency, solubility, mass and volume, students learn how to classify materials scientifically. The chapter also builds the important concept that anything occupying space and having mass is called matter.
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