Chemistry Class 10 Chapter 15 Important MCQs Federal Board
Chemistry Important MCQs
Class 10 Chapter 15
Environmental Chemistry 2 MCQ’S
1. It has been estimated that the total amount of water present on earth is about ____ cubic kilometers.
A.1.33 Billion
B.1.33 Million
C.1.33 Trillion
D. None of them
Answer: A (1.33 Billion)
2. Water covers nearly ___ % of Earth’s crust.
A.65
B.54
C.71
D.80
Answer: C (71%)
3. Freshwater present to man is only ___ % of the total amount of water.
A.3.2
B.2.2
C.1.2
D.0.2
Answer: D (0.2%)
4. Water’s density is maximum at ___ .
A.4˚C
B.7 ˚C
C.9 ˚C
D.11 ˚C
Answer: A (4 ˚C)
5. Water is a ___ conductor of electricity.
A. Good
B. Poor
C. Very good
D. None of them
Answer: B (Poor)
6. Water molecules are strongly attracted to ions and polar molecules with which water can form _____.
A. Hydrogen bonds
B. Sulphide bonds
C. Molar bonds
D. Infrared bonds
Answer: A (Hydrogen bonds)
7. Water that does not form scum and easily gives a lather with soap is called ___ water.
A. Dirty
B. Rough
C. Soft
D. Hot
Answer: C (Soft)
8. Water that forms scum or gives a little lather is called __ water
A. Soft
B. Rough
C. Hot
D. Hard
Answer: D (Hard)
9. CO2 reacts with water to form ____ acid.
A. Acetic
B. Carbonic
C. Sulphuric
D. Aesthetic
Answer: B (Carbonic)
10. The presence of which of the following dissolved salts causes the water to become hard?
A. CaSO4.2H2O, CaSO4, MgSO4.H2O
B. NaCl, KCl
C. HKl , BeCl
D. None of them
Answer: A (CaSO4.2H2O, CaSO4, MgSO4.H2O)
11. Temporary hardness can be removed by ____.
A. Rubbing
B. Erasing
C. Cooling
D. Boiling
Answer: D (Boiling)
12. Temporary hardness is caused by dissolved ___ and ___ bicarbonates.
A. Carbon, Silicon
B. Calcium, Magnesium
C. Hydrogen, Oxygen
D. None of them
Answer: B (Calcium, Magnesium)
13. The presence of dissolved ____ and ____ of calcium and magnesium causes permanent hardness.
A. Sulphate, Carbides
B. Sodium, Chloride
C. Sulphates , Chlorides
D. None of them
Answer: C ( Sulphates , Chlorides)
14. Hard water ___ cleansing action of soap.
A. Increases
B. Elevates
C. Hampers
D. Discourages
Answer: C (Hampers)
15. Scum is also known as ____.
A. Soda
B. Acid
C. Base
D. White precipitate
Answer: D (White precipitate)
16. Detergents do not react with ___ and ____ ions present in hard water.
A. Calcium, Magnesium
B. Carbon, Oxide
C. Nitrogen, Sulphate
D. None of them
Answer: A (Calcium, Magnesium)
17. Which of the following method can’t be used on a large scale to remove the temporary hardness of water?
A. Clark’s method
B. By adding slaked lime
C. Boiling
D. None of them
Answer: C (Boiling)
18. Slaked lime reacts with bicarbonates to form insoluble ____ and remove the temporary hardness of the water.
A. Carbides
B. Acids
C. Bases
D. Carbonates
Answer: D (Carbonates)
19. On a large scale permanent hardness of water can be removed by ______.
A. By adding water
B. By adding washing soda
C. By adding fruits
D. By adding salts
Answer: B (By adding washing soda)
20. Which of the following is one of the natural ion exchanger?
A. Sodium
B. Chloride
C. Zeolite
D. Neon
Answer: C (Zeolite)
21. Zeolite is chemically _____.
A. Sodium chloride
B. Potassium chloride
C. Beryllium chloride
D. Sodium aluminum silicate
Answer: D (Sodium aluminum silicate)
22. The used-up zeolite can be regenerated by a heating concentrated solution of ____.
A. NaCl
B. BeCl
C. KCl
D. HO
Answer: A (NaCl)
23. Which of the following infectious diseases are caused by the bacterial contents present in water?
A. Cholera, jaundice
B. Dengue, Corona
C. Fever, Cold
D. Coughing, Sour throat
Answer: A (Cholera, jaundice)
24. Chromium (VI) ions are highly toxic and known to cause ____.
A. Cholera
B. Dysentery
C. Cancer
D. None of them
Answer: C (Cancer)
25. Gelatinous mass of aluminum hydroxide is formed as a result of which process?
A. Sedimentation
B. Coagulation
C. Filtration
D. Chlorination
Answer: B (Coagulation)
26. Chlorine reacts with water and forms ____ acid.
A. Hydrochloric
B. Hypochlorous
C. Acetic
D. Carbonic
Answer: B (Hypochlorous)
27. Cholera is an ___ disease.
A. Intestinal
B. Respiratory
C. Circulatory
D. Nervous
Answer: A (Intestinal)
28. Hepatitis is an acute inflammation of ___.
A. Lungs
B. Heart
C. Legs
D. Liver
Answer: D (Liver)
29. Salmonella typhi and paratyphi cause which of the following disease?
A. Cholera
B. Heart Attack
C. Typhoid
D. Jaundice
Answer: C (Typhoid)
30. Water in swimming pools is purified by ___ and ____.
A. Detergents
B. Aeration, Chlorination
C. Fertilization
D. None of them
Answer: B (Aeration, Chlorination)
31. There is about ___ % NaCl in sea water.
A.4
B.7
C.2.3
D.3.4
Answer: D (3.4%)
32. In jaundice excess of ___ from the liver enters into the blood and causes yellowness of skin and eyes.
A. Glucagon
B. Pepsin
C. Bile
D. None of them
Answer: C (Bile)
33. Hepatitis A and E are spread through _____.
A. Eating junk food
B. Polluted water
C. Healthy food
D. Pure water
Answer: B (Polluted water)
34. Dysentery is caused by ____.
A. Viruses
B. Bacteria
C. Parasite
D. None of them
Answer: C (Parasite)
35. Which of the following infection is transmitted by faecal contamination of water or food by an encysted organism?
A. Cholera
B. Typhoid
C. Dysentery
D. Hepatitis
Answer: C (Dysentery)
36. Cholera is not effective against viruses such as those that cause ____.
A. Typhoid
B. Cholera
C. Cancer
D. Hepatitis
Answer: D (Hepatitis)
37. ___ water wastes a lot of soap when used for washing.
A. Hard
B. Soft
C. Rough
D. Dirty
Answer: A (Hard)
38. Water is also known as ________.
A. Universal solute
B. Universal solvent
C. Zeolite
D. Universal reactor
Answer: B (Universal solvent)
39. The splitting of water molecules produces ___ amount of hydrogen as compared to oxygen.
A. Triple
B. Quadruple
C. Double
D. None of them
Answer: C (Double)
40. The ratio of hydrogen and oxygen in water is in the ratio of ____by volume.
A.2:1
B.1:2
C.3:1
D.4:1
Answer: A (2:1)
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