Air around us Worksheet-3

Air around us Worksheet-3

Multiple-Choice Question:

21. __________ is needed for burning.

(a) Oxygen                                       (b) Argon            

(c) Carbon dioxide                         (d) Nitrogen

22. Air contains:

(a) water vapour                             (b) oxygen

(c) dust and smoke                         (d) all of these

23. Air is made up of:

(a) three gases                                 (b) one gas

(c) several gases                              (d) none of these

24. Main causes of air pollution are:

(a) vehicles releasing smoke         (b) excessive burning of fuels

(c) burning of wood                        (d) all of these

25. Gas with the highest percentage in air is:

(a) Nitrogen                                     (b) Oxygen

(c) Water vapour                            (d) Carbon dioxide

26. Air contains _______% of carbon dioxide.

(a) 30.00              (b) 0.030            (c) 3.000              (d) 0.003

27. What percentage of Earth’s water is fresh?

(a) 20%                (b) 3%                  (c) 10%                (d) 5%

28. What is the name for the smaller stream that flows into a larger stream?

(a) Delta              (b) Tributary        (c) Valley             (d) Peninsula

29. What is the source of hydrological or water cycle?

(a) Sun                 (b) Wind              (c) Rain                (d) Snow

30. What is the process by which vapour becomes a liquid?

(a) Precipitation                              (b) Infiltration

(c) Evaporation                                (d) Condensation

Answer Key:

21. (a)
22. (d)
23. (c)
24. (d)
25. (a)
26. (b)
27. (b)
28. (b)
29. (a)
30. (d)