Q21 of 32 Page 106

Fill in the blanks with the help of words given in the bracket after each sentence.

(1) When air is contaminated by ________ substances which have a ________ effect on both the ________ and _______, it is referred to as ________.


(2) 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 ).


(3) While ________ your teeth, leaving the ______ running may waste several ______ of water.


(tap, litres, brushing, washing, drops ).


(4) Water which is suitable for _______ is called _______ water.


(washing, bathing, drinking, potable, soft).


(5) Water which looks clean still has disease carrying _______ and _______ impurities.


(insects, micro organism, particles, dissolved, harmful).


1. unwanted, harmful, living, non-living, air pollution.

2. industries, air, refineries, gaseous, sulphur dioxide, nitrogen dioxide.


3. brushing, tap, litres


4. drinking, potable


5. microorganisms, dissolved.


More from this chapter

All 32 →
19

A lot of dry leaves are collected in a school garden and burnt every day. Do you think that it is right to do so? If not, what should we do to dispose off the dry leaves?

 20

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

 22

Match the items of Column A with those of Column B. Table

 23

Find out the wrong statements and write them in their correct form.

(1) We can survive for some time without air but we cannot survive even for a few minutes without food.


(2) A brick kiln emits lot of smoke and other harmful gases causing air pollution.


(3) Carbon monoxide is produced by complete burning of fuels such as coal, petrol, diesel.


(4) Chlorination is a commonly used chemical method for killing germs in water.


(5) Water which is suitable for drinking is called soft water.