Page 205 - New Medley 5 Semester 2

 Air pressure is also used to ll ink in a fountain pen.

 Moving liquids from one container to other using a siphon is a common

practice in our day to day life. is makes use of air pressure exerted on the
surface of liquid.

1 • Remembering

Fill in the blanks.

1. is the thick layer of air present around the earth.
2. Carbon dioxide is given out as a result of in animals.

3. e soil x the nitrogen with other elements.

4. helps to ll a doctor’s syringe.

AIR POLLUTION

e presence of unwanted and harmful materials in the air is called air pollution.

e unwanted substances are called pollutants. Smoke and dust are the main
pollutants of air. ey are very harmful to plants and animals.

Sources of Air Pollution

 Burning of fossil fuels releases carbon
dioxide and other harmful gases into the

air.

 Industries release smoke containing many
harmful gases.

 Rotting garbage and open drains release
gases having foul smell.

 Automobiles release harmful substances
like oxides of nitrogen and sulphur.

 Aeroplanes and spacecra s release lots of
smoke in the air. Sources of air pollution

Effects of Air Pollution
 Air pollution causes allergies, irritation of eyes, nose, throat and diseases like

asthma, bronchitis and respiratory disorders.

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