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Pollution of Air and Water

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 can not be
easily identified, e.g.– agricultural run off, acid rain etc.
(i) How do you classify the various sources of water pollution?
(ii) What are the point sources of water pollution?
(iii) Name any two non-point sources of water pollution?

02/11/2024

Science

8th

Pollution of Air and Water

How can we reduce, reuse and recycle water?

02/11/2024

Science

8th

Pollution of Air and Water

Explain the traditional way of purifying water to make it fit for drinking.

02/11/2024

Science

8th

Pollution of Air and Water

We should plant trees and nurture the ones already present in the neighbourhood. Why?

02/11/2024

Science

8th

Pollution of Air and Water

Why is it advised that industries should switch over to cleaner
fuels such as CNG and LPG in the Taj Mahal Zone in Agra?

02/11/2024

Science

8th

Pollution of Air and Water

What do CFCs stand for? Name some devices where CFCs are used. Why CFCs are considered as pollutants?

02/11/2024

Science

8th

Pollution of Air and Water

In the following statements, the underlined words are jumbled
up. Write them in their correct form.
(a) Air contains 78% ginroten and 21% gonexy.
(b) Vehicles produce high level of pollutants like carbon dioxide,
nitrogen oxides, nobrac moondexi and mosek.
(c) Carbon dioxide, thaneme, nitrous oxide and water vapour
are known as heengrouse sesga.
(d) Gangotri glacier in Himalaya has started melting because of
lablog ringwam.
(e) Whenever harmful substances such as wagese, toxic
chemicals, silt, etc. get mixed with water, the water becomes
potdulle.

02/11/2024

Science

8th

Pollution of Air and Water

. Find out the wrong statements and write them in their correct
form.
(a) We can survive for some time without air but we cannot survive
even for a few minutes without food.
(b) A brick kiln emits lot of smoke and other harmful gases
causing air pollution.
(c) Carbon monoxide is produced by complete burning of fuels
such as coal, petrol, diesel.
(d) Chlorination is a commonly used chemical method for killing
germs in water.
(e) Water which is suitable for drinking is called soft water.

02/11/2024

Science

8th

Pollution of Air and Water

Fill in the blanks with the help of words given in bracket after each sentence.
(a) When air is contaminated by ________ substances which have a ________ effect on both the ________ and ________, it is referred
to as ________.(air pollution, harmful, living, unwanted, non-living,pollutants).
(b) Many ________ are responsible for causing ________ pollution.
Petroleum ________ are a major source of ________ pollutants
like ________ and ________.
(sulphur dioxide, refineries, industries, nitrogen dioxide,
gaseous, liquid, people, air).
(c) While ________ your teeth, leaving the ________ running may waste several ________ of water.
(tap, litres, brushing, washing, drops)
(d) Water which is suitable for _________ is called ________ water.
(washing, bathing, drinking, potable, soft).
(e) Water which looks clean still has disease carrying ________and ________ impurities. (insects, microorganism, particles, dissolved, harmful).

02/11/2024

Science

8th

Pollution of Air and Water

The level of air pollution is higher at a busy traffic intersection. Why?

02/11/2024

Science

8th