ICSE Worksheet for Chapter - 12 Pollution of Air and Water Class 8

Worksheets For class 8

Find ICSE Worksheet for chapter-12 Pollution of Air and Water class 8

CLASS-8

BOARD: ICSE

BIOLOGY Worksheet - 12

TOPIC: Pollution of Air and Water

For other ICSE Worksheet for class 8 Science check out main page of Physics Wallah.

1. Dead remains of animals and plants added in a water body causes ___________.

2. ___________ and ___________ are two common water-borne diseases.

3. Percentage of nitrogen in air is –

(a) 77.02%

(b) 78.09%

(d) 74.09%

4. Which one of the following forms a stable compound with haemoglobin?

(a) SO₂

(b) CO₂

(d) O₂

5. Which of the following is not a greenhouse gas?

(a) Carbon dioxide

(b) Sulphur dioxide

(d ) Nitrogen

6. How does CO₂ content rise in the atmosphere and become excessive?

7. Explain the differences between pure air and polluted air.

8. Explain circumstances leading to acid rain. How does acid rain affect us?

9. Describe the threat to the beauty of the Taj Mahal.

10. Why does the increased level of pollutants in the water affect the survival of aquatic organisms?

Solutions: to worksheet-12 Topic- Pollution of Air and Water

1. Water pollution

2. Cholera and Typhoid

3. (b) 78.09%

4. (c) CO

5. (d) Nitrous Oxide

6. Due to deforestation, the CO₂ levels are rising in the atmosphere. Morever industries release hydrocarbons and other particulate pollutants which mix with atmosphere and increase the CO₂ is a green house gas which traps the heat in the earth’s surface.

Pure Air

Polluted Air

(a) The air which does not contain any

harmful pollutant is called pure air

(b) The air that we breathe near forests is

pure air.

(b) The air which contains harmful pollutants

is called polluted air.

(b) The air that we breathe near automoibiles

and industrial areas is polluted air.

8. Sulphur dioxide combines with water vapours to produce sulphuric acid which corrodes metals and etches marble. This sulphuric acid comes down with water as ‘Acid Rain’. It causes damage to plants and other organisms. In humans, it might cause skin pigmentation. It also damages rare monuments and buildings.

9. Case study on Taj Mahal:

• The industries located in and around Agra like rubber processing, automobile, chemicals and especially the Mathura oil refinery, have been responsible for producing pollutants like SO₂ and NO₂.

• These gases react with the water vapour present in the atmosphere to form sulphuric acid and nitric acid. This acid drops down with rain making the rain acidic. This is called Acid Rain.

• Acid rain corrodes the marble of the movement. The phenomenon is called ‘Marble cancer’.

• Suspended particulate matter, such as the soot particles emitted by Mathura oil refinery has contributed towards the yellowing of the marble.

• The Supreme Court has taken several steps to save the Taj. It has ordered industries to switch to cleaner fuels like CBG and LPG. Morever, the automobiles should switch over to unleaded petrol in the Taj zone.

10. The increased level of pollutants in the water, effect her survival of aquatic organisms due to organic pollutants lead to bacterial growth which reduces the amount of oxygen dissolved in water and this in turn kills the fish and destroys the aquatic life.