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Class 6 Science: Materials Around Us, 8 practice questions with answers

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These are 8 practice questions on Class 6 Science Chapter 6, Materials Around Us, of the new NCERT textbook, Curiosity. Each has a worked answer and the textbook page it comes from. They cover lustre and why some metals look dull, hard and soft as relative properties, choosing transparent, translucent or opaque materials for a job, soluble and insoluble materials, the difference between mass and volume, what counts as matter, and writing the units of mass and volume. Try each one before you open the answer.

These questions are our own, drafted with AI help, and every answer was checked against the textbook page it cites, but no practising teacher has reviewed them yet. If you find a mistake, please tell us.

What the chapter says you need

Facts from the NCERT textbook (Curiosity: Textbook of Science for Grade 6, Chapter 6, printed pages 101 to 121):

Appearance and hardness

Question 1. Aman finds an old iron nail that looks dull and brownish. He says, "Iron is a non-lustrous material." Find his mistake.

Answer: iron is a metal, and metals are lustrous; this nail has only lost its shine. Some metals lose their lustre and start to look dull because of the effect of air and moisture on them, so the lustre is often seen only on a freshly cut surface. If Aman rubs a small part of the nail with sandpaper, the fresh surface underneath shines. (Lustrous and non-lustrous materials, page 107.)

Question 2. Ravi scratches a bar of soap, a bamboo stick and a glazed tile with a steel key. The key leaves a deep mark on the soap, a light scratch on the bamboo and no mark on the tile. He says, "The bamboo got scratched, so bamboo is a soft material, just like soap." Find his mistake.

Answer: hard and soft are relative; bamboo is hard compared with soap but soft compared with the tile. Materials that are scratched easily are soft, and those that are difficult to scratch are hard, but these properties are relative. The soap was scratched most easily and the tile not at all, so the order from softest to hardest is soap, bamboo, tile. Bamboo is harder than soap, even though it is softer than the tile, just as rubber is harder than sponge but softer than iron. (Hard and soft materials, page 107.)

Seeing through, and dissolving

Question 3. Which kind of material (transparent, translucent or opaque) would you choose for each, and why? (a) a lunch-box lid through which you can check what is inside without opening it, (b) the door of a room where people change clothes, (c) a lampshade that lets light through but softens the glare of the bulb.

Answer: (a) transparent, (b) opaque, (c) translucent. (a) Through a transparent material, such as clear glass or clear plastic, things can be seen clearly, so the food is visible. (b) Through an opaque material, such as wood, nothing can be seen, which keeps the room private. (c) Through a translucent material, such as butter paper, things are seen but not clearly; it lets some light through without showing the bright bulb clearly. (Transparent, translucent and opaque materials, pages 108 and 109.)

Question 4. Tanvi stirs a spoonful of a white powder into a glass of water. The water turns cloudy, and after some time the powder settles at the bottom. Her friend says, "The powder mixed with the water, so it dissolved." Find the mistake.

Answer: the powder is insoluble; it did not dissolve. A soluble material completely disappears when it is mixed in water. Tanvi's powder can still be seen: first as the cloudiness and then as a layer at the bottom. Materials that do not disappear even after a long stir are insoluble in water. (Soluble and insoluble materials, page 111.)

Mass, volume and matter

Question 5. Bag A is filled to the top with cotton wool. Bag B, the same size, is only half filled with sand. Ravi says, "Bag A takes up more space, so it must have more mass." Find his mistake. How can he find out which has more mass?

Answer: taking up more space means more volume, not more mass; he should weigh both bags on a balance. The space that something occupies is its volume, so the cotton wool in Bag A has the greater volume. Mass tells how heavy or light something is, and it is found by weighing. The half bag of sand is very likely the heavier of the two, but the way to be sure is to compare the bags on a balance. (Mass, page 113; volume, page 114.)

Question 6. Which of these are matter: a pencil, a glass of milk, the steam rising from a kettle, the shadow of a tree? Explain.

Answer: the pencil, the milk and the steam are matter; the shadow is not. Anything that occupies space and has mass is matter. The pencil and the milk both take up space and have mass. Steam is water in the form of a gas: it still takes up space and has mass, so it is matter too. A shadow is only a dark patch where light is blocked; it has no mass and takes up no space, so it is not matter. (What is matter, page 115.)

Question 7. Sunil writes in his notebook: "The bag has 3 Kgs. of rice and the jug holds 650 ml of water." Correct the way he has written the units.

Answer: "3 kg" and "650 mL". Kilogram is written as kg, in lower case, with no full stop after the symbol (except at the end of a sentence) and with no "s" for more than one, and a space is left between the number and the unit. Millilitre is written as mL, with a lower-case m and a capital L. So the sentence should read: "The bag has 3 kg of rice and the jug holds 650 mL of water." (Writing units of mass and volume, page 115.)

Question 8. Which holds more water: a bottle labelled 750 mL, or three glasses that each hold 220 mL?

Answer: the 750 mL bottle. The number on the label is the volume of water the bottle holds. Three glasses of 220 mL hold 3 × 220 = 660 mL in all. Since 660 mL is less than 750 mL, the bottle holds more, by 750 − 660 = 90 mL. (Volume and the mL labels on bottles, page 114; units of volume, page 115.)

Questions students ask

What is the difference between a material and an object? An object is a thing we use, such as a chair or a pen; a material is any substance used to make it, such as wood, plastic or metal. An object can be made of one material or of several, and one material can be used to make many objects. (Pages 102 to 104.)

What does lustrous mean? A lustrous material has a shiny surface. Such materials are usually metals, such as iron, copper and aluminium, while paper, wood, rubber and jute are non-lustrous. (Page 107.)

Why do we classify materials? Grouping materials by their properties helps us study them and see patterns in how they look and behave. (Pages 103 and 116.)

Practise more, and check your marks

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Sources

All opened and read on 22 October 2026. Page numbers are the printed page numbers of the textbook; printed page = PDF page + 100.

The facts are from the textbook pages above. The questions, worked answers and checks are our own, and every number was re-computed by script. This guide is general information; follow your teacher and the textbook.