NCERT Class VIII Science Solutions: Chapter 18-Pollution of Air and Water Part 6

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Question 30:

How can we reduce, reuse and recycle water?

Answer:

The various ways to conserve water (or save water) at home are as follows.

  • Reduce – While brushing your teeth, bathing etc. we should not keep our taps on. We should turn off the tab immediately after use. The leaking taps should be repaired immediately.

  • Reuse – Water used for washing vegetables, rice etc. can be used for gardening.

  • Recycle – Dirty water can be recycled after purification

Image of importance of the 3Rs

Image of Importance of the 3Rs

Image of importance of the 3Rs

Question 31:

Read the paragraph and answer the questions following it.

Water is essential for life. Without water there would be no life. We usually take water as granted for its purity, but we must ensure the quality of water. Pollution of water originates from human activities. Through different paths, pollution reaches to ground water. Easily identified source or place of pollution is called as point source, e.g. – municipal and industrial discharge pipes, where pollutants enter the water source. Non–point sources of pollution are those where a source of pollution cannot be easily identified, e.g. – agricultural run-off, acid rain etc.

  1. How do you classify the various sources of water pollution?

  2. What are the point sources of water pollution?

  3. Name any two non-point sources of water pollution?

Answer:

    1. Point sources

    2. Non–print sources

  1. Easily identified source or place of pollution is called point source e.g. municipal, industrial discharge pipe etc.

  2. Agricultural run-off, acid rain.

Question 32:

Complete the crossword puzzle with the help of clues given below:

Result for Complete the crossword puzzle (Q)

Complete the Crossword Puzzle (Q)

Result for Complete the crossword puzzle (Q)

Across and Down
Across and down

Across

Down

1. Pollutant which was used in refrigerators and air conditioners. (18)

2. This layer protects us from harmful ultraviolet rays. (5)

3. Produced on incomplete combustion of fuels. (14)

4. It is essential for combustion. (6)

6. This chemical protects our crops and is washed into water bodies from the field. (9)

5. Disease which is caused by drinking

Contaminated water. (7)

7. River which is famous in India and sustains most of the northern, central and eastern Indian population. (5)

Answer:

Result for Complete the crossword puzzle (A)

Complete the Crossword Puzzle (A)

Result for Complete the crossword puzzle (A)

Crosswords Hints
Crosswords hints

Across

Down

1. Pollutant which was used in refrigerators and air conditioners - chlorofluorocarbon

2. This layer protects us from harmful ultraviolet rays - Ozone

3. Produced on incomplete combustion of fuels – Carbon monoxide

4. It is essential for combustion - Oxygen

6. This chemical protects our crops and is washed into water bodies from the field - Pesticide

5. Disease which is caused by drinking

Contaminated water - Cholera

7. River which is famous in India and sustains most of the northern, central and eastern Indian population - Ganga

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