Chemistry Class 10 Chapter 15 Important MCQs Federal Board

Chemistry Class 10 Chapter 15 Important MCQs Federal Board

Chemistry Important MCQs

Class 10 Chapter 15

Environmental Chemistry 2 MCQ’S

environmental chemistry
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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.





Answer: C (71%)

3. Freshwater present to man is only ___ % of the total amount of water.





Answer: D (0.2%)

4. Water’s density is maximum at ___ .


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


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.





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.





Answer: A (2:1)

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