NCERT Class VI Science Solutions: Chapter 4 – Fibre to Fabric Part 5

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LONG ANSWER QUESTIONS

Question 22:

Chalk, iron nail, wood, aluminium, candle, cotton usually look different from each other. Give some properties by which we can prove that these materials are different.

Answer:

Material and Charecterstics
Material and charecterstics

Materials

Properties

Chalk

Rough on the surface, cannot be Compressed

Iron Nail

Shine (Lustre), hard

Aluminum

Shine (Lustre), hard

Wood

Hard to compress, dull appearance

Candle

Soft to Compress

Cotton

Soft to compress

Question 23:

Why do you think oxygen dissolved in water is Important for the survival of aquatic animals and plants?

Answer:

Oxygen gas dissolved in water, oxygen gas is soluble in water. The plants and animals which live in water use the oxygen dissolved in water for respiration. Thus, oxygen gas dissolved in water is very important for the survival of animals and plants that live in water.

Question 24:

Differentiate among opaque, translucent and transparent materials, giving one example of each.

Answer:

Opaque those materials through which we cannot see at all are called opaque materials e.g. car board.

Translucent those materials through which we cannot see clearly are called translucent materials e.g. Butter paper.

Transparent those materials through which we can see clearly are called transparent materials e.g. Glass.

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Transparent, Translucent and Opaque

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Question 25:

Sugar, salt, mustard oil, sand, sawdust, honey, chalk powder, petals of flower, soil, copper sulphate crystals, glucose. Wheat flour are some substances given to Paheli. She wants to know whether these substances are soluble in water or not. Help her in Identifying soluble and insoluble substances in water.

Answer:

Soluble in water – Sugar, Salt, Honey, Copper sulphate, crystals, Glucose.

Insoluble in water - Mustard oil, Sand, Sawdust, Chalk, powder, Soil, Petals of flower, Wheat flour