NCERT Solutions — Materials Around Us (Class 6)

📘 NCERT Solutions — Materials Around Us (Class 6, Chapter 6)

📖 In-text Questions (1–5)

Question 1. Would it be a good idea to use paper-like materials for making cooking utensils? (Page 104)

Answer:
🔥 No. Paper-like materials are not suitable for making cooking utensils. Such materials cannot withstand high temperature of the flame and may burn. The liquid contents of the food will also soak the paper.

Question 2. Are all lustrous materials metals?

Answer:
✨ All lustrous materials may not be metals. Some materials can be made lustrous by polishing or coating them with a thin layer of plastic, wax or any other material which makes them look shiny.

Question 3. Is water transparent? Can it be made opaque?

Answer:
💧 Pure water is transparent. It can be made opaque by adding some other materials to it. For example, muddy water is opaque.

Question 4. Does everything you put in water disappear?

Answer:
❌ No. Everything we put in water does not disappear. Only the materials which are soluble in water disappear when mixed with water in limited amount.

Question 5. Are there any properties which can be shown by all materials? If yes, what are those?

Answer:
⚖️ Yes, there are some properties which are shown by all materials. All material objects possess mass and occupy space.

📝 Exercise Questions (1–10)

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:
🍲 Pulses such as moong dal, chana dal, urad dal, arhar dal, etc., should be grouped together.
🌾 Cereals such as rice, dalia, wheat flour, maize flour, etc., should be grouped together.
🌶️ Spices such as red chilli powder, salt, clove, black pepper, ajwain, cumin (jeera), coriander seeds (dhaniya), turmeric powder, garam masala etc., should be grouped together.
🛢️ Cooking oils and ghee such as mustard oil, soyabean oil, olive oil, cow ghee, etc., should be grouped together.
🍯 Jams and squashes should be placed together.

Question 2. Unscramble the letters (Column I) and match with their properties (Column II).

Answer:
(i) MATTER — (b) Occupies space and has mass ⚖️
(ii) SOLUBLE — (d) Mixes completely in water 💧
(iii) TRANSPARENT — (a) Objects can be seen clearly 👀
(iv) LUSTRE — (c) Shiny surface ✨

Question 3. The containers which are used to store materials in shops and at home are usually transparent. Give your reasons for this.

Answer:
📦 The containers which are used to store materials in shops and at home are usually transparent so that the materials stored in them can be seen through them and can be found easily.

Question 4. State whether the statements given below are True [T] or False [F], Correct the False statements).

Answer:
(i) Wood is translucent while glass is opaque. — ❌ False. Wood is opaque while glass is transparent.
(ii) Aluminium foil has lustre while an eraser does not. — ✅ True.
(iii) Sugar dissolves in water whereas sawdust does not. — ✅ True.
(iv) An apple is a matter because it occupies no space and has mass. — ❌ False. An apple is a matter because it occupies space and has mass.

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 fulfill these properties the most?

Answer:
(i) Hardness (does not bend or shake on sitting even after long use). → 💪 Iron, cement and stones
(ii) Lightweight (easy to lift or to take from one place to another). → 🪶 Plastic and bamboo
(iii) Does not feel very cold when sitting during winters. → 🔥 Wood and bamboo
(iv) Can be cleaned regularly and made to look new even after long use. → 🧽 Plastic, iron, cement and stones

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:
🗑️ We can use plastic containers for collection of (i) food waste (ii) broken glass and (iii) waste paper. These containers may have different colours because food waste is biodegradable, broken glass is hazardous and waste paper is recyclable.
🥗 For food waste → the material of the container should not react with food and should be leak proof.
🪟 For broken glass → the material of the container should be hard so that glass should not cut it.
📄 For storing waste paper → the material of the container should be light and strong.

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

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:
🔹 X can be sugar crystal and Y can be rubber block.
⚖️ The material X is hard.
🧽 The material Y is soft.

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) steel
(b) rubber
(c) sugar
(d) cardboard or plywood
(e) air

(ii) Example:
(a) You can see clearly through me → 👓 Glass
(b) I am soft → ☁️ Cotton
(c) I am non-lustrous → 🪨 Chalk
(d) I am liquid and insoluble in water → 🛢️ Oil
(e) I cannot be compressed easily → 🧱 Stone

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:
💧 Soluble pairs:
(i) Water and glucose
(ii) Water and vinegar

🚫 Insoluble pairs:
(i) Water and mustard oil
(ii) Water and wheat flour