RBSE Solutions Class 6 Science Chapter 6 Materials Around Us

Materials Around Us Class 6 Question Answer - InText

Question 1. Would it be a good idea to use paperlike materials for making cooking utensils?
Answer: No, it would not be a good idea to use paper-like materials for cooking utensils. This is because the choice of material for any object depends on its properties and what it will be used for. Paper is flammable and would burn or melt when heated, making it unsuitable for cooking. It also absorbs liquids, which would be messy and unhygienic for food. Therefore, materials that can withstand high temperatures and are non-absorbent, like metals, are chosen for cooking utensils.
In simple words: Paper is not good for cooking pots because it burns easily and gets wet. We choose materials based on what we need them to do.

🎯 Exam Tip: When answering questions about material suitability, always mention the specific properties of the material and how they relate to the object's purpose.

Question 3. Does everything you put in water disappear?
Answer: No, not everything you put in water disappears. Some materials, like sugar or salt, dissolve completely in water, meaning they mix so well that you cannot see them anymore. Other materials, like sand or oil, do not dissolve; they either sink to the bottom or float on the surface, and you can still see them. Even if a substance dissolves, it doesn't "disappear" in the sense of vanishing; it just spreads out evenly in the water.
In simple words: No, some things dissolve in water and disappear, like sugar. Other things, like sand, do not dissolve and stay visible.

🎯 Exam Tip: Remember to differentiate between dissolving (mixing evenly) and disappearing (vanishing) when explaining substances in water.

Question 4. Are there any properties which can be shown by all materials? If yes, what are those?
Answer: Yes, there are properties that all materials exhibit. Two universal properties shown by all materials are mass and volume. Mass is the amount of matter in an object, and volume is the amount of space an object takes up. Every physical object, whether a solid, liquid, or gas, has both mass and volume. Even a tiny speck of dust or a large mountain possesses these fundamental characteristics.
In simple words: Yes, all materials have two things in common: mass (how much stuff is in them) and volume (how much space they take up).

🎯 Exam Tip: For universal properties, focus on fundamental physical characteristics that apply to all states of matter.

RBSE Class 6th Science Chapter 6 Question Answer - Exercise

Let Us Enhance Our Learning

Question 1. Visit your kitchen and observe how your parents have organised various edibles. Can you suggest a better sorting method? Write it in your notebook.
Answer: In most kitchens, things are stored in an organized way, such as keeping all spices together in one place, and pulses and grains in another. This makes it easy to find what is needed quickly. To improve this, one could also sort items by how often they are used (daily items easily accessible), by expiry date (older items in front), or by type of food (all baking ingredients together). A well-organized kitchen helps in efficient cooking and reduces waste.
In simple words: Kitchens usually store similar things together, like all spices. A better way could be to put things you use often in easy reach, or group items by when they expire.

🎯 Exam Tip: When suggesting improvements, think about practical benefits like ease of access, safety, and preventing spoilage.

Question 2. Unscramble the letters (Column I) and match with their properties (Column II).
Column-l
(i) TREMAT
Column-II
(a) Objects can be seen clearly through it.
Answer:

🎯 Exam Tip: For unscrambling and matching, identify the core concept of the jumbled word first, then look for the property that best describes it.

Question 3. The containers which are used to store materials in shops and at home are usually transparent. Give your reasons for this.
Answer: Containers used in shops and homes are often transparent so that the items stored inside can be easily seen. This allows people to quickly identify what is in the container without opening it, which saves time and effort. In shops, transparent containers attract customers as they can see the quality of the product. At home, it helps in quickly finding ingredients or supplies. This makes organization and retrieval much simpler for everyone.
In simple words: Containers are clear so you can easily see what is inside without opening them. This helps you find things faster in shops and at home.

🎯 Exam Tip: When explaining design choices, connect them to practical benefits for the user (convenience, identification, visual appeal).

Question 4. State whether the statements given below are True [T] or False [F]. Correct the False statement(s).
(i) Wood is translucent while glass is opaque.
(ii) Aluminium foil has lustre while an eraser does not.
(iii) Sugar dissolves in water whereas sawdust does not.
(iv) An apple is a matter because it occupies no space and has mass.
Answer:
(i) False, wood is opaque while glass is transparent.
(ii) True
(iii) True
(iv) False, an apple is a matter because it occupies space and has mass.
In simple words: We check if each sentence is true or false. If it's false, we fix it. For example, wood blocks light, making it opaque, and glass lets light through, making it transparent. An apple is matter because it takes up space and has weight.

🎯 Exam Tip: Pay close attention to definitions of terms like translucent, opaque, transparent, and matter. Correct false statements by reversing the incorrect property or term.

Question 5. We see chairs made up of various materials, such as wood, iron, plastic, bamboo, cement and stones. Following are some desirable properties of materials which can be used to make chairs. Which materials used to make chairs fulfil these properties the most?
(i) Hardness (does not bend or shake on sitting even after long use).
(ii) Lightweight (easy to lift or to take from one place to another).
(iii) Does not feel very cold when sitting during winters.
(iv) Can be cleaned regularly and made to look new even after long use.
Answer:
(i) Hardness: Materials like wood, iron, cement, and stone provide good hardness, preventing chairs from bending or shaking. Wood is a popular choice for its balance of hardness and workability.
(ii) Lightweight: Plastic and bamboo are good choices for lightweight chairs that are easy to move. These materials make chairs portable and convenient for various settings.
(iii) Does not feel very cold when sitting during winters: Wood and bamboo are excellent for this property as they do not conduct heat quickly, making them feel warmer. Unlike metals or stone, they are comfortable to sit on in cold weather.
(iv) Can be cleaned regularly and made to look new even after long use: Plastic chairs are very easy to clean and can maintain their appearance for a long time. Metal chairs can also be cleaned well, especially if treated to prevent rust. Wood, if properly sealed, can also be quite durable and maintain its look.
In simple words: Different materials are best for different chair features. Wood and iron make strong chairs. Plastic and bamboo make light chairs. Wood and bamboo are warm to sit on. Plastic is easy to clean and keeps looking new.

🎯 Exam Tip: For questions about material properties, consider specific examples and explain how each material's characteristic meets the desired criteria.

Question 6. You need to have containers for collection of (i) food waste, (ii) broken glass and (iii) wastepaper. Which materials will you choose for containers of these types of waste? What properties of materials do you need to think of?
Answer:
1. For food waste, a light and strong container is needed. The material should also not get spoiled by moisture from the food. Plastic would be a good choice for this container as it is waterproof and durable. Plastic also prevents leaks and keeps odors contained.
2. For broken glass, a container made of a hard and strong material is essential to prevent injury. Iron or a thick, sturdy plastic bin would be suitable for this. This material ensures that sharp glass pieces do not cut through the container.
3. For wastepaper, a light container is sufficient. A container made of paper or cardboard is suitable, as it is easy to handle and can be recycled along with the paper. This aligns with reducing waste.
In simple words: For food waste, choose plastic because it's strong and doesn't get wet. For broken glass, use strong metal or thick plastic to be safe. For wastepaper, a light paper or cardboard box is fine.

🎯 Exam Tip: When selecting materials for specific uses, always list the key properties required and justify your choice based on those properties.

Question 7. Air is all around us but does not hinder us from seeing each other. Whereas, if a wooden door comes in between, we cannot see each other. It is because air is __________ and the wooden door is __________ . Choose the most appropriate option:
(i) transparent, opaque
(ii) translucent, transparent
(iii) opaque, translucent
(iv) transparent, translucent
Answer: (i) transparent, opaque
In simple words: Air lets us see through it easily, so it's transparent. A wooden door blocks our view completely, so it's opaque.

🎯 Exam Tip: Understand the definitions: Transparent allows clear vision, translucent allows some blurred vision, and opaque blocks all vision.

Question 8. Imagine you have two mysterious materials, X and Y. When you try to press material X, it feels rigid and does not change its shape easily. On the other hand, material Y easily changes its shape when you press it. Now, when you mix both materials in water, only material X dissolves completely, while material Y remains unchanged. What can materials X and Y be? Can you identify whether material X is hard or soft? What about material Y? Justify your answer.
Answer: Material X could be something like sugar or salt because it is rigid, does not change shape easily, and dissolves completely in water. This means material X is hard. Material Y could be something like sand or wax because it easily changes shape when pressed and does not dissolve in water. This means material Y is soft. The dissolving property further helps distinguish them as soluble and insoluble substances respectively.
In simple words: Material X is hard, like sugar, because it's stiff and dissolves in water. Material Y is soft, like sand or wax, because it's easy to press and doesn't dissolve in water.

🎯 Exam Tip: Break down the properties described (rigidity, compressibility, solubility) and match them to common materials. Clearly state whether each material is hard or soft based on the provided clues.

Question 9. (i) Who am I? Identify me on the basis of the given properties.
(a) I have lustre.
(b) I can be easily compressed.
(c) I am hard and soluble in water.
(d) You cannot see clearly through me.
(e) I have mass and volume but you cannot see me.
(ii) Make your own 'Who am I?'
Answer:
(i)
(a) Metal (Metals are known for their shine and reflective surfaces.)
(b) Rubber (Rubber is flexible and can be squeezed easily, making it compressible.)
(c) Sugar (Sugar is a solid, hard crystal that dissolves completely in water.)
(d) Butter paper (Butter paper is translucent; you can see light through it but not clear images.)
(e) Air (Air is a gas, so it has mass and volume, but it is invisible to the naked eye.)
(ii) Who am I?
(a) I am liquid and insoluble in water: Oil (Oil does not mix with water and floats on top.)
(b) I make things shiny: Polish (Polishes are used to create a glossy surface on various objects.)
(c) I can be seen through: Glass (Glass is transparent, allowing clear vision through it.)
(d) I am a gas and I am soluble in water: Oxygen (Oxygen dissolves in water, which is vital for aquatic life.)
In simple words: We identify materials by their features. For example, something shiny is usually metal. Something that squishes easily is rubber. Invisible things that take up space are gases like air. We can also create new riddles, like a liquid that doesn't mix with water is oil.

🎯 Exam Tip: For "Who am I?" questions, analyze each property carefully and think of the most common material that fits all clues. For creating your own, ensure the properties clearly define a specific material.

Question 10. You are provided with the following materials-vinegar, honey, mustard oil, water, glucose and wheat flour. Make any two pairs of materials where one material is soluble in the other. Now, make two pairs of materials where one material remains insoluble in the other material.
Answer:
1. One ingredient is soluble in the other:
(i) Vinegar, Water (Vinegar is mostly water, and its active component, acetic acid, mixes perfectly with water.)
(ii) Glucose, Water (Glucose is a type of sugar that readily dissolves in water, forming a clear solution.)
2. One ingredient is insoluble in the other:
(i) Mustard Oil, Vinegar (Mustard oil does not mix with vinegar; it forms separate layers.)
(ii) Wheat Flour, Water (Wheat flour does not truly dissolve in water; it forms a suspension, making the water cloudy, and eventually settles.)
In simple words: Some things mix completely (soluble), like vinegar in water or glucose in water. Other things don't mix at all (insoluble), like oil in vinegar or flour in water.

🎯 Exam Tip: Remember that "soluble" means one substance completely dissolves into another, forming a uniform mixture, while "insoluble" means it does not.

RBSE Class 6 Science Chapter 6 Important Questions

Multiple Choice Questions

Question 2. Sponge is a-
(a) hard material
(b) type of a metal
(c) soft material
(d) type of rough material
Answer: (c) soft material
In simple words: A sponge feels soft when you touch it. It can be easily squeezed and changed in shape.

🎯 Exam Tip: Think about the physical characteristics (like how it feels or bends) to determine if a material is hard or soft.

Question 3. Which of the following is non soluble in water?
(a) Vinegar
(b) Lemon juice
(c) Kerosene oil
(d) None of the options
Answer: (c) Kerosene oil
In simple words: Kerosene oil does not mix with water; it forms a separate layer. Vinegar and lemon juice, however, mix well with water.

🎯 Exam Tip: Soluble means it dissolves, non-soluble means it doesn't. Remember common examples like oil and water not mixing.

Question 4. Is not a translucent material-
(a) Oily paper
(b) Glass
(c) Butter paper
(d) X-ray sheet
Answer: (b) Glass
In simple words: Translucent materials let some light pass through but you can't see clearly. Glass, however, is transparent, meaning you can see clearly through it.

🎯 Exam Tip: Glass is transparent, not translucent. Translucent materials include butter paper, oily paper, or frosted glass.

Question 5. Soluble in water-
(a) Kerosene
(b) Coconut oil
(c) Mustard oil
(d) Vinegar
Answer: (d) Vinegar
In simple words: Vinegar mixes completely with water. Kerosene, coconut oil, and mustard oil do not mix with water.

🎯 Exam Tip: Most oils are insoluble in water. Vinegar, being an aqueous solution itself, readily mixes with water.

Question 7. Is not a transparent material-
(a) Glass
(b) Metal
(c) Water
(d) Air
Answer: (b) Metal
In simple words: Metal does not allow light to pass through it, so you cannot see through it. Glass, water, and air all let you see through them.

🎯 Exam Tip: Transparent materials allow light to pass through them clearly. Metals are opaque; they block light entirely.

Question 8. An example of hard substance is-
(a) sponge
(b) wood
(c) cotton
(d) candle
Answer: (b) wood
In simple words: Wood is a hard material that is difficult to press or scratch. Sponge, cotton, and candle wax are soft materials.

🎯 Exam Tip: Hard substances resist changes in shape and are difficult to compress or scratch.

Question 9. The meaning of 'snigdha' is-
(a) unctuous
(b) soft
(c) rough
(d) hot
Answer: (a) unctuous
In simple words: 'Snigdha' means oily or greasy. It describes something that feels smooth and slippery, like oil.

🎯 Exam Tip: This is a vocabulary-based question. 'Unctuous' refers to being oily or greasy, which aligns with 'snigdha'.

Question 10. The material not suitable for making glass is-
(a) Paper
(b) Glass
(c) Plastic
(d) Metal
Answer: (a) Paper
In simple words: Paper is not used to make glass because glass is already glass itself. Plastic and metal are other materials that could be used for containers but are not used to form glass itself.

🎯 Exam Tip: This question might be confusing as "Glass" is an option. The question asks what material is *not suitable for making glass*, and glass itself is a material, not something you "make glass" from. Paper is completely unsuitable for creating glass.

Question 1. The method of arranging objects into groups is called __________ .
Answer: classification
In simple words: When we put things into groups based on how they are similar, it's called classification.

🎯 Exam Tip: Classification is a fundamental concept in science for organizing information and objects based on shared characteristics.

Question 2. Anything that occupies space and has mass is called __________ .
Answer: matter
In simple words: Anything that takes up room and has weight is called matter.

🎯 Exam Tip: Remember the two key properties of matter: it occupies space (volume) and has mass.

Question 3. The space occupied by matter is its __________ .
Answer: volume
In simple words: How much space something takes up is called its volume.

🎯 Exam Tip: Volume is a measure of the three-dimensional space an object occupies.

Question 4. Mass quantifies the amount of __________ present in an object.
Answer: matter
In simple words: Mass tells us how much 'stuff' an object is made of.

🎯 Exam Tip: Mass is an intrinsic property that measures an object's inertia and the amount of substance it contains.

Question 5. The materials through which we are not able to see at all are called __________ .
Answer: opaque
In simple words: Materials you cannot see through at all are called opaque.

🎯 Exam Tip: Distinguish clearly between opaque (blocks all light), transparent (allows clear vision), and translucent (allows some light, blurry vision).

Question 6. Objects are made from a large variety of __________ .
Answer: materials
In simple words: Things we use are made from many different kinds of materials.

🎯 Exam Tip: The world is full of diverse materials, each with unique properties suited for different uses.

True/False

Question 1. All substances dissolve in water. (True/False)
Answer: False
In simple words: Not everything dissolves in water. Some things do, like salt, but others don't, like sand.

🎯 Exam Tip: Remember examples of insoluble substances (e.g., oil, sand) to quickly identify this statement as false.

Question 2. Substances that have shine or lustre are generally metals. (True/False)
Answer: True
In simple words: Things that look shiny are usually metals. This shine is a property called lustre.

🎯 Exam Tip: Lustre is a characteristic property often associated with metals, though some non-metals can also be shiny.

Match the words given in Column-I with Column-II

Question 1.

🎯 Exam Tip: Clearly understand the definitions of optical properties (transparent, opaque, translucent) and solubility for accurate matching.

Question 2.

🎯 Exam Tip: For material matching questions, recall the primary characteristic of each substance (e.g., glass is transparent, sugar is soluble) to make accurate pairings.

Very Short Answer Type Questions

Question 1. What is called 'material'?
Answer: A material is the substance or mixture of substances that is used to make an object. Everything around us is made of different materials, each with its own specific properties. For instance, plastic, wood, and metal are all common materials.
In simple words: 'Material' is what an object is made from, like wood or plastic.

🎯 Exam Tip: Define material simply as "what objects are made of" and give a couple of common examples.

Question 2. What are all objects made of?
Answer: All objects are made of some kind of material. These materials can be natural or man-made and include substances like cotton, wood, cloth, glass, sand, clay, plastic, and metal. The choice of material depends on the object's purpose and desired properties. Every item we use, from a simple pencil to a complex machine, is composed of one or more materials.
In simple words: All objects are made from different materials like wood, plastic, or glass.

🎯 Exam Tip: When listing examples, try to include a variety of materials from different categories (natural, synthetic, solid, etc.).

Question 3. Why can't a glass made of cloth be used to store water?
Answer: A glass made of cloth cannot be used to store water because cloth is absorbent and porous. Water would simply seep through the fabric, making it unsuitable for holding liquids. Materials chosen for containers like glasses must be waterproof and non-absorbent to serve their purpose effectively. That's why glass, metal, or plastic are used instead.
In simple words: A cloth glass can't hold water because cloth soaks up water and lets it leak out.

🎯 Exam Tip: Focus on the properties of the proposed material (cloth - absorbent, porous) and how they contradict the object's function (glass - holding water).

Question 5. Why are different materials used to make balls of different games?
Answer: Different materials are used to make balls for different games because each game has specific requirements for the ball's properties. These properties include bounce, size, and weight, which vary greatly from one sport to another. For example, a golf ball needs to be hard and dense for a long flight, while a soccer ball needs to be lighter and have a specific air pressure for kicking. The material ensures the ball behaves correctly during play.
In simple words: Balls for different games are made from different materials because each game needs a ball with special bounce, size, and weight.

🎯 Exam Tip: Connect the material properties directly to the functional requirements of the ball in a specific sport (e.g., hardness for golf, weight for soccer).

Question 6. Give examples of metals?
Answer: Examples of common metals include iron, copper, aluminium, and gold. These materials are widely used in various applications due to their properties such as conductivity, malleability, and lustre. Metals are essential in industries ranging from construction to electronics.
In simple words: Iron, copper, aluminium, and gold are all examples of metals.

🎯 Exam Tip: When asked for examples, provide a few common and recognizable ones.

Question 7. Which are the 'soft' substances?
Answer: Soft substances are materials that can be easily compressed, bent, or scratched. Examples of soft substances include cotton, sponge, and rubber. These materials change shape with little force, making them useful for items like cushioning or cleaning. Their flexibility is a key characteristic.
In simple words: Soft substances are things that are easy to squeeze or scratch, like cotton or a sponge.

🎯 Exam Tip: Define soft substances by how they react to pressure (easily compressed, scratched) and give clear examples.

Question 8. What are hard substances?
Answer: Hard substances are materials that are difficult to compress or scratch. They maintain their shape and structure even when force is applied. Examples include wood, stone, and iron. These substances are valued for their durability and resistance to deformation. Hardness makes them suitable for building structures and tools.
In simple words: Hard substances are materials that are tough to squeeze or scratch, like wood or stone.

🎯 Exam Tip: Define hard substances by their resistance to compression or scratching and provide relevant examples.

Question 9. Some metals often lose their lustre. Why does this happen?
Answer: Metals often lose their lustre, or shiny appearance, due to the effects of air and moisture. This process is called corrosion or tarnishing. When metals react with oxygen and water in the environment, they form a dull layer of oxides or other compounds on their surface. For example, iron rusts, and silver tarnishes, both losing their original shine. Regular cleaning or protective coatings can help maintain their shine.
In simple words: Metals lose their shine because air and moisture react with them, causing a dull layer to form on the surface.

🎯 Exam Tip: The key reason for metals losing lustre is a chemical reaction with the environment (oxidation, tarnishing) due to air and moisture.

Question 11. What is a 'substance'?
Answer: A substance is a pure form of matter with a uniform composition and distinct properties. It can be an element or a compound. Examples include water, sugar, salt, iron, and oxygen. Each substance has unique characteristics that define it. Unlike mixtures, substances cannot be separated into simpler components by physical means.
In simple words: A 'substance' is a pure type of material, like water, sugar, or oxygen. It has its own special features.

🎯 Exam Tip: Emphasize "pure form of matter" and "uniform composition" when defining a substance.

Question 12. What is 'terracotta'?
Answer: Terracotta is a type of ceramic, specifically a clay-based unglazed ceramic material. It is made from baked clay, which gives it a distinct brownish-red color. Terracotta has been used for centuries to create pottery, sculptures, and building materials like roof tiles and bricks. Its durability and natural aesthetic make it a versatile material.
In simple words: Terracotta is baked clay, usually reddish-brown. People use it to make pots, statues, and building parts.

🎯 Exam Tip: Key points for terracotta are "baked clay" and its use in pottery/building materials.

Question 13. Can we use different materials to make different parts of an object?
Answer: Yes, we can definitely use different materials to make different parts of an object. This is often done to take advantage of the specific properties of each material, making the object more functional or durable. For example, a pen typically has a plastic body, a metal clip, and ink inside. Each material serves a unique purpose. Similarly, a bicycle uses metal for the frame, rubber for the tires, and plastic for the grips.
In simple words: Yes, we can use different materials for different parts of an object. For example, a pen uses plastic, metal, and ink.

🎯 Exam Tip: Give a clear example (like a pen or bicycle) where multiple materials contribute to an object's overall function.

Question 14. What properties can different materials have?
Answer: Different materials can have a wide range of properties. These include physical properties like lustre (shininess), hardness (resistance to scratching or compression), softness, shape, and color. They can also have properties like transparency (allowing light to pass through), solubility (ability to dissolve), and texture (how they feel). These varied properties determine how materials are used in everyday life. For example, shiny metals are used for jewelry, while soft cotton is used for clothes.
In simple words: Materials can be shiny, hard, soft, clear, colored, or dissolve in water. Each material has its own special features.

🎯 Exam Tip: List a diverse set of properties (optical, mechanical, chemical) to show a comprehensive understanding.

Question 15. What is the role of water in the functions of our body?
Answer: Water plays a vital role in numerous functions of our body. It acts as a solvent, dissolving many materials that are transported throughout the body, such as nutrients and waste products. Water helps regulate body temperature, lubricates joints, and protects organs and tissues. It is essential for all chemical reactions occurring within the body. Therefore, staying hydrated is crucial for overall health.
In simple words: Water is very important for our body. It helps carry nutrients, removes waste, controls body temperature, and helps our body work properly.

🎯 Exam Tip: Highlight water's roles as a solvent, transporter, temperature regulator, and participant in bodily processes.

Question 16. Are gases soluble in water?
Answer: Yes, some gases are soluble in water. For instance, oxygen gas dissolves in water, which is crucial for aquatic life to breathe. Carbon dioxide also dissolves in water, forming carbonic acid, which is important for carbon cycle and affects ocean acidity. However, the solubility of gases in water can vary greatly depending on the type of gas, temperature, and pressure. Cooler water generally holds more dissolved gas.
In simple words: Yes, some gases can dissolve in water. For example, oxygen dissolves in water, which fish need to live.

🎯 Exam Tip: Provide a key example (oxygen for aquatic life) to illustrate the concept of gas solubility in water.

Question 18. What is crucible?
Answer: A crucible is a type of container or vessel used for melting substances at very high temperatures. It is typically made from heat-resistant materials like clay or iron, which can withstand extreme heat without melting or reacting with the contents. Crucibles are commonly used in metallurgy, chemistry, and other scientific applications where materials need to be heated to their melting points. They are essential tools for processes like smelting and alloying metals.
In simple words: A crucible is a strong pot, usually made of clay or iron, used to melt things at very high heat.

🎯 Exam Tip: Key points are "vessel for melting substances" and "made of heat-resistant materials like clay and iron."

Short Answer Type Questions

Question 1. On the basis of the property of compressibility, in how many types can substances be classified? Explain with examples.
Answer: On the basis of compressibility, substances can be classified into two main types:
(i) Soft substances: These are materials that can be easily compressed, squeezed, or scratched. They change their shape with little applied force. Examples include cotton, sponge, and rubber. Softness often makes these materials suitable for cushioning or comfort. For example, a sponge is very easily compressed.
(ii) Hard substances: These are materials that cannot be easily compressed or scratched. They resist changes in their shape and maintain their structure even under pressure. Examples include wood, stone, and metal beads. Hardness makes these materials suitable for construction and tools. For instance, you cannot easily press a piece of wood. The ability to compress or not helps distinguish materials greatly.
In simple words: Substances can be soft (easy to squeeze, like cotton or sponge) or hard (tough to squeeze or scratch, like wood or stone).

🎯 Exam Tip: Clearly define each category (soft/hard) based on compressibility and provide at least two distinct examples for each.

Question 2. Are all shiny objects metals?
Answer: No, not all shiny objects are metals. While many metals possess a characteristic shiny surface (lustre), other materials can also be made to look shiny through various processes. For example, some surfaces are made shiny by polishing them or by coating them with thin layers of plastic, wax, or other reflective materials. These coatings give a non-metal object a metallic appearance without it actually being a metal. Therefore, shininess alone is not a definitive test for identifying metals. For example, a polished piece of plastic can also look shiny.
In simple words: No, not all shiny things are metals. Some non-metals can be made to look shiny by polishing them or adding a thin coating.

🎯 Exam Tip: Be precise: "generally metals" is true, but "all shiny objects are metals" is false. Give examples of how non-metals can achieve a shine.

Question 3. Do liquids like oil, vinegar, honey dissolve in water?
Answer: Whether liquids like oil, vinegar, and honey dissolve in water depends on the specific liquid. Some liquids, such as vinegar, mix completely with water to form a uniform solution; these are called miscible liquids. Honey also mixes and dissolves in water. However, other liquids, like oil, do not mix with water and will form a separate layer when left undisturbed. These are called immiscible liquids. This property is due to the different molecular structures and polarities of the liquids.
In simple words: Vinegar and honey mix completely in water. Oil does not mix with water and stays in a separate layer.

🎯 Exam Tip: Distinguish between miscible (mixes completely, like vinegar/honey) and immiscible (does not mix, like oil) liquids when discussing solubility.

Question 4. What can be found out from the mass of the material in an object?
Answer: The mass of the material in an object tells us the amount of matter present in that object. It is a fundamental property that quantifies how much "stuff" an object is made of, regardless of its size or shape. Knowing the mass helps in understanding an object's inertia (resistance to change in motion) and its weight when gravity acts upon it. It also helps in comparing the density of different materials. For example, a heavier object has more mass than a lighter one, assuming similar volumes.
In simple words: The mass of an object tells us how much material is inside it. It helps us know how much 'stuff' an object has.

🎯 Exam Tip: Mass is a measure of the quantity of matter, not volume or weight, although it's related to both. Focus on "amount of matter."

Question 5. Differentiate between mass and volume.
Answer:

🎯 Exam Tip: Clearly state what each property measures and list their standard units. Mass is about quantity of matter; volume is about space occupied.

Question 6. Differentiate between 'lustrous' and 'non-lustrous' materials.
Answer:

🎯 Exam Tip: Define each term by its surface appearance (shiny vs. dull) and provide clear examples of materials for both categories.

Question 7. Differentiate between 'soluble' and 'non-soluble' materials.
Answer:

🎯 Exam Tip: Define solubility as the ability to dissolve completely and form a uniform mixture. Provide common examples for both soluble and insoluble substances.

Long Answer Type Questions

Question 1. What is classification? Objects are classified on the basis of their properties. Explain with examples.
Answer: Classification is the process of putting objects into groups. This is done by looking at how similar or different their properties are. For example, in a kitchen, utensils that are alike are usually stored together. Similarly, spices are kept in one corner, and pulses and grains in another. This makes things easy to find. Grouping helps us understand and manage many different items more easily.
In simple words: Classification is when we sort objects into groups based on what they are like or unlike. This helps us to keep things organized.

🎯 Exam Tip: When explaining classification, always provide clear, everyday examples like sorting kitchen items to illustrate the concept effectively.

Question 2. Explain transparent, opaque and translucent materials with examples.
Answer:
(i) Transparent materials- These are materials through which we can see things very clearly. For instance, glass, water, air, and cellophane paper are all transparent materials.
(ii) Opaque materials- These materials do not allow us to see through them at all. Examples of opaque materials include wood, cardboard, and metals.
(iii) Translucent materials- Through these materials, objects can be seen, but not very clearly. They make things look blurry. Butter paper and frosted glass are good examples of translucent materials. Each type allows different amounts of light to pass through.
In simple words: Transparent means you can see clearly through it, opaque means you cannot see through it at all, and translucent means you can see through it a little, but not clearly.

🎯 Exam Tip: Remember to clearly define each term and provide at least two common examples for each to score full marks.

Question 3. What do you understand by ORS? How is it prepared?
Answer: ORS stands for Oral Rehydration Solution. It is used to treat dehydration, which can happen due to diarrhea or other sicknesses. Ready-made ORS packets are available at health centers and in shops. These packets contain a mix of salts and sugar that, when dissolved in clean water, help the body to absorb fluids and essential salts. It's a simple, life-saving remedy.
In simple words: ORS is a special drink to help people who are dehydrated, often from sickness. You mix a powder packet with water to make it.

🎯 Exam Tip: Highlight that ORS is crucial for treating dehydration and mention its availability and composition (salts and sugar).

Question 4. Explain the classification system that existed in ancient India with the help of an example.
Answer: Ancient India also had systems for classifying things. Ayurveda, which is a traditional Indian medical system, used a method for grouping everything. It described all physical matter using 20 properties, which were ten pairs of opposite qualities (called 'guna'). These properties could also describe all living things, like plants, animals, and humans, as well as the environment and even food. For example, some properties included 'guru' (heavy), 'laghu' (light in weight), 'manda' (slow), 'tikshna' (quick or fast), 'hima' (cold), and 'uchna' (hot). This showed a deep understanding of the natural world.
In simple words: Ancient India, especially in Ayurveda, grouped things using 20 opposite properties like heavy/light or hot/cold. These properties described everything from matter to living things.

🎯 Exam Tip: When discussing ancient Indian classification, remember to mention Ayurveda and provide a few examples of the 'guna' (properties) to make your answer comprehensive.

Essay Type Questions

Question 1. In what way were the pottery made in ancient Indian subcontinent? What was the purpose of making these pottery?
Answer: The earliest pottery in the Indian subcontinent was found in areas like the Ganga plains (Lahuradewa) and Baluchistan (Mehrgarh), dating back 7,000 to 8,000 years ago. By around 4000 BCE, people in the Sindhu Sarasvati region began to use new techniques. They started making pottery on wheels, adding colors, applying protective or decorative coats called 'slips', and painting designs. These methods became even more advanced during the Harappan Civilization (2600-1900 BCE), when they made bright red pots with black geometric and animal designs. The clay for these pots, dishes, and bowls was carefully chosen, cleaned, sieved, kneaded, and then baked in kilns (this baked clay is called Terracotta). Pottery served many purposes, from cooking food to storing grains, oil, and ghee. This widespread use highlights their importance in daily life.
In simple words: Ancient Indians made pottery using wheels, colors, and baking clay. They used these pots for cooking and storing food.

🎯 Exam Tip: When describing ancient pottery, focus on the techniques (wheel-turned, painted, baked) and key purposes (cooking, storage) to provide a clear picture.

Question 2. Comment - (i) Unit of mass, (ii) Unit of volume.
Answer:
(i) Unit of mass- The standard unit of mass in the International System of Units (SI) is the kilogram. It is written as kg. When writing 'kg', there should be no space between 'k' and 'g', and no full stop after the symbol unless it is at the end of a sentence. Also, always leave a space between the number and the unit when writing a mass value, for example, 5 kg, not 5kg. The kilogram is a base unit, meaning it's fundamental to many measurements.
(ii) Unit of volume- The standard unit of volume in the International System of Units (SI) is the cubic meter (\(m^3\)). However, for liquids, volume is commonly measured in liters (L) and milliliters (mL). One liter is equal to 1000 milliliters. It's important to use the correct units based on the state of matter being measured.
In simple words: The unit for mass is kilograms (kg). The unit for volume, especially for liquids, is liters (L) and milliliters (mL).

🎯 Exam Tip: Remember to specify 'kilogram' for mass and 'liter' or 'cubic meter' for volume, also recalling to leave a space between the numerical value and the unit (e.g., 5 kg, not 5kg).

Question 3. Describe the main properties of materials?
Answer: Materials have various properties that are important for their uses. The main properties are:
(1) Appearance- Different materials look different. Some materials have shiny, lustrous surfaces, like metals, while others are dull and non-lustrous, such as paper or wood.
(2) Hardness and soft- Some materials are soft and can be easily compressed or scratched, like cotton. Other materials are hard and difficult to compress or scratch, like stone.
(3) Solubility- Some materials dissolve in water and are called soluble, like sugar. Other materials do not mix with water and remain visible even after stirring; these are called insoluble materials, such as sand.
(4) Transparency- This property describes how much light passes through a material. Transparent materials allow clear vision through them (e.g., glass). Opaque materials do not allow any light to pass through (e.g., wood). Translucent materials allow some light to pass, but objects seen through them are not clear (e.g., butter paper). These properties help us choose the right material for specific tasks.
In simple words: Materials have properties like how they look (shiny or dull), how hard they are, if they dissolve in water, and if light can pass through them.

🎯 Exam Tip: To describe material properties fully, define each property (appearance, hardness, solubility, transparency) and provide examples for each type.

RBSE Class 6 Science Chapter 6 Notes

Class 6 Science Chapter 6 Notes RBSE - Materials Around Us Class 6 Notes

• All objects are made of some material, such as paper, wood, cloth, glass, metal, plastic, clay etc.
• An object can be made up of a single material or a combination of different materials. We can use different materials to make objects with similar functions.
• The method of arranging objects into groups is called classification. Objects can be divided into groups on the basis of their similar properties.
• Some materials are soluble in water while others are insoluble.
• Anything that occupies space and has mass is called matter.
• The space occupied by matter is its volume.
• Mass quantifies the amount of matter present in an object.