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a ee, 1, Multiple Choice Questions, Paces 2092292, (a) (iv) (b) (iii), , (e) (ii) () (i) ie), , (d) (1H), , g. Fill in the blanks, 0m (ny cy, (a) 78 (b) Oxygen (e) thin (d) wind, (e) oxygen (f)_ nitrogen (9) Aquatic (hy ox,, , 3. Write True or False, —, (a) False (b) True (c) True (d) True, (e) True (f) True (9) True (h) False, , 4, (a) Observe the given figure and answer the question, , The empty glass is actu, , ally filled with air,, form of bubbles and water gets fi cee, , (b) Carefully observe the diagram gi, (i) For anything to burn, Oxygen gas is essential,, Candle ‘A keeps burning because it is, , (ii) Candle ‘BY gets extinguished after so, As soon as the oxygen, extinguished., , 5. Given below is a diagram showin, the gases in the boxes provided., 21% of Oxygen, 1% of Other gases, 0.03% of Carbon dioxide, 78% of Nitrogen, , 6. Give reasons for the following., , lting the glass, the air comes out in the, lled in the glass,, , ven alongside and answer the questions that follow,, , getting a continuous supply of oxygen., me time because it is covered with a jar., Present inside the jar is used up by the candle, it gets, , g the percentage of gases in the air. Fill in the names of, , (a) Carbon dioxide gas is produced during burning of things. It is toxic for human beings, in high concentration and causes suffocation. It is for this reason that we feel suffocated, when something is burning in a closed room., , (b) Earthworms come out of the soil during rains because water fills all the air spaces in, the soil and there is no air for earthworms to breathe., , (c) Deep sea divers carry oxygen cylinders with them because humans cannot breathe, in oxygen dissolved in water., , in ai id not through the mouth because, (d) We must always breathe in air through our nose and not, our nose has fine hair and mucus, which trap dust particles and prevent them from, , entering our body., 7. Very short answer type questions., (a) Wind, (b) Nitrogen, (c) 0.03%, (a) Nitrogen, (e) Air helps gliders, sailboats and aeroplanes to move., , 8. Short answer type questions. ~ =, (a) The amount of water vapour present in the air is called humidity., , bt al i neeeenemteernnmemnnmmrersceneecren,, , Scanned with CamScanner