Lakhmir Singh Solutions - Science - Class 8 solutions for Chapter 18 Pollution Of Air And Water

Name the gas present in the atmosphere which is mainly responsible for causing global warming.

Name two gases present in polluted air which can cause acid rain.

Name all the major pollutants of air.

Which air pollutant combines with the haemoglobin of our blood?

Name the various air pollutants discharged by motor vehicle exhausts.

Which gas in the upper atmosphere prevents ultraviolet radiations of the sun from reaching the earth?

Name any two diseases caused by drinking polluted water containing sewage.

Name any four toxic metals whose compounds are present in industrial wastes.

Name any two types of chemicals used in agriculture which cause water pollution.

The use of excessive fertilizers in the fields lead to the deficiency of an important substance in the water of a nearby lake. Name the substance.

What is the Ganga Action Plan? When and why was it launched?

Name any four pollutants which cause water pollution. State any three ways of controlling water pollution.

How do industries cause water pollution?

How can you help reduce air pollution at the individual level?

Explain the difference between pure air and polluted air.

What is 'greenhouse effect'? State its importance for us.

Name two greenhouse gases? Which one of them produces the maximum greenhouse effect?

What depletes the ozone layer in the atmosphere? What are the harmful effects of the depletion of the ozone layer on us?

Name one source and one harmful effect of each of the following air pollutants:

(a) Sulphur dioxide.

(b) Nitrogen oxides.

(c) Carbon monoxide.

(d) Chlorofluorocarbons (CFCs)

Explain why, even clear, transparent and odourless water may not always be safe for drinking.

Explain why hot water released by power plants and industries is considered a pollutant.

Why does the increased level of nutrients (or fertilizers) in the lake water affect the survival of aquatic organisms (like fish)?

Explain how the use of pesticides in agriculture causes water pollution.

(a) Describe the threat to the Taj Mahal monument due to air pollution.

(b) State any two ways of controlling air pollution;

(a) What is potable water? Name any two methods to make water safe for drinking. (b) State two ways in which you conserve water at home by preventing its wastage.

(a) What is meant by water pollution? What are the different ways in which water gets polluted?

(b) State the harmful effects of water pollution.

(a) What is air? Write the names of various constituents of air.

(b) What is air pollution? What are the main sources of air pollution?

What is smog? How is smog formed? What are its harmful effects?

What is acid rain? How is acid rain caused? What are the harmful effects of acid rain?

What is global warming? What are the likely harmful effects of global warming?

Which of the following is not a greenhouse gas?

(a) Carbon dioxide

(b) Nitrous oxide

(c) Methane

(d) Nitrogen

Which of the following air pollutant reduces the oxygen-carrying capacity of blood to a large extent?

(a) Carbon dioxide

(b) Nitrogen monoxide

(c) Carbon monoxide

(d) Sulphur dioxide

The constituent of polluted air which contributes to producing acid rain is:

(a) Nitrogen

(b) Sulphur dioxide

(c) Oxygen

(d) Argon

The Kyoto protocol is associated with one of the following. This one is:

(a) Reduction in the use of chlorofluorocarbons

(b) Reduction in the emission of greenhouse gases

(c) Reduction in the cutting of forest trees

(d) Reduction in the pollution of freshwater sources

Which of the following will be reduced in the air in a city forest when a lot of dust and fly ash is emitted by a coal-based factory in the vicinity?

(a) Nitrogen

(b) Carbon dioxide

(c) Oxygen

(d) Water vapour

Which of the following disease cannot be caused by the drinking of river water contaminated with untreated sewage?

(a) Cholera

(b) Typhoid

(c) Tuberculosis

(d) Diarrhoea

Which of the following statement about ozone is correct?

(a) It is essential for breathing

(b) It absorbs ultraviolet rays

(c) Its proportion of air is about 3%

(d) It is mainly responsible for global warming

Drinking water can be made safe by adding one:

(a) Aspirin tablet

(b) Iodine tablet

(c) Chlorine tablet

(d) Chlorophyll tablets

The excessive use of one of the following in agriculture can cause the death of fish in a pond by oxygen starvation. This one is:

(a) Fertilizers

(b) Manures

(c) Pesticides

(d) Herbicides

Which of the following is usually not a water pollutant?

(a) Sewage

(b) Fertiliser

(c) Fly ash

(d) Pesticide

Which of the following are used in electric water filters to kill all the harmful microorganisms present in tap water and make it safe for drinking?

(a) Infrared radiation

(b) Gamma radiation

(c) Visible radiation

(d) Ultraviolet radiation

Which of the following is not an air pollutant?

(a) Sulphur dioxide

(b) Sewage

(c) CFC's

(d) SPM

Which of the following air pollutant is capable of preventing photosynthesis in plants?

(a) CFC's

(b) Nitrogen oxides

(c) Dust

(d) Carbon monoxide

One of the following does not contribute to producing acid rain. This one is:

(a) Nitrogen dioxide

(b) Nitrogen monoxide

(c) Carbon monoxide

(d) Sulphur dioxide

Which of the following will reach the earth in greater amounts if the number of chlorofluorocarbons released into the air increases?

(a) Infrared rays

(b) X-rays

(c) Gamma rays

(d) Ultraviolet rays

Lakhmir singh solutions science class 8 Solutions for Chapter 18 pollution of air and water