100 Important Chemistry Questions & Answers | Class 6 ICSE | Full Chapter Revision

 100 Important Chemistry Questions & Answers | Class 6 ICSE | Full Chapter Revision

Introduction to Chemistry

1. What is the definition of chemistry?
a) Study of plants
b) Study of matter and its changes ✅
c) Study of planets
d) Study of animals

2. Chemistry is important because it helps us understand:
a) The behavior of matter ✅
b) The behavior of animals
c) The movement of planets
d) The laws of physics

3. Which of the following is NOT an application of chemistry?
a) Food preservation
b) Medicine
c) Music ✅
d) Agriculture

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Development of Chemistry & Notable Chemists

4. Who is known as the Father of Modern Chemistry?
a) John Dalton
b) Antoine Lavoisier ✅
c) Dmitri Mendeleev
d) Robert Boyle

5. Which scientist proposed the atomic theory?
a) Antoine Lavoisier
b) John Dalton ✅
c) Dmitri Mendeleev
d) J.J. Thomson

6. Who is credited with developing the periodic table?
a) Antoine Lavoisier
b) Dmitri Mendeleev ✅
c) John Dalton
d) Robert Boyle

7. What was Robert Boyle’s major contribution to chemistry?
a) Boyle’s law ✅
b) Atomic theory
c) Discovery of oxygen
d) Periodic table

8. Which scientist discovered oxygen?
a) Marie Curie
b) Joseph Priestley ✅
c) John Dalton
d) Robert Boyle

9. Prafulla Chandra Ray is known for his work in:
a) Organic chemistry
b) Inorganic chemistry ✅
c) Nuclear chemistry
d) Physical chemistry

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Role of Chemistry in Daily Life

10. Chemistry is involved in which of the following industries?
a) Cement
b) Paint
c) Medicine
d) All of the above ✅

11. What is the role of chemistry in food preservation?
a) Prevents food from spoiling ✅
b) Changes food color
c) Makes food taste bad
d) Removes vitamins

12. Which chemical is used in food preservation?
a) Sodium chloride ✅
b) Ammonium nitrate
c) Sulfuric acid
d) Hydrogen peroxide

13. What is the role of chemistry in medicine?
a) Helps develop drugs ✅
b) Cures diseases
c) Both A and B ✅
d) None of the above

14. Which of these is an example of a chemical used in cosmetics?
a) Sulfur ✅
b) Sodium chloride
c) Carbon dioxide
d) Ammonium sulfate

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Common Chemicals and Their Uses

15. Which gas is used in the making of POP (Plaster of Paris)?
a) Oxygen
b) Carbon dioxide
c) Sulfur dioxide
d) None of the above ✅

16. Which material is used to make glass?
a) Silica (SiO₂) ✅
b) Sodium chloride
c) Calcium carbonate
d) Hydrochloric acid

17. Which of the following is used in making soap?
a) Fatty acids and sodium hydroxide ✅
b) Carbon dioxide and water
c) Hydrogen and nitrogen
d) Calcium carbonate

18. What is the main chemical used in plastics?
a) Polymers ✅
b) Ammonium sulfate
c) Sodium chloride
d) Copper sulfate

19. Cement is made from:
a) Limestone ✅
b) Copper
c) Plastic
d) Sugar

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Introduction to Chemistry

1. What is the definition of chemistry?
a) Study of plants
b) Study of matter and its changes ✅
c) Study of planets
d) Study of animals

2. Chemistry is important because it helps us understand:
a) The behavior of matter ✅
b) The behavior of animals
c) The movement of planets
d) The laws of physics

3. Which of the following is NOT an application of chemistry?
a) Food preservation
b) Medicine
c) Music ✅
d) Agriculture

---

Development of Chemistry & Notable Chemists

4. Who is known as the Father of Modern Chemistry?
a) John Dalton
b) Antoine Lavoisier ✅
c) Dmitri Mendeleev
d) Robert Boyle

5. Which scientist proposed the atomic theory?
a) Antoine Lavoisier
b) John Dalton ✅
c) Dmitri Mendeleev
d) J.J. Thomson

6. Who is credited with developing the periodic table?
a) Antoine Lavoisier
b) Dmitri Mendeleev ✅
c) John Dalton
d) Robert Boyle

7. What was Robert Boyle’s major contribution to chemistry?
a) Boyle’s law ✅
b) Atomic theory
c) Discovery of oxygen
d) Periodic table

8. Which scientist discovered oxygen?
a) Marie Curie
b) Joseph Priestley ✅
c) John Dalton
d) Robert Boyle

9. Prafulla Chandra Ray is known for his work in:
a) Organic chemistry
b) Inorganic chemistry ✅
c) Nuclear chemistry
d) Physical chemistry

10. Who discovered the process of electrolysis?
a) Antoine Lavoisier
b) Humphry Davy ✅
c) Dmitri Mendeleev
d) John Dalton

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Role of Chemistry in Daily Life

11. Chemistry is involved in which of the following industries?
a) Cement
b) Paint
c) Medicine
d) All of the above ✅

12. What is the role of chemistry in food preservation?
a) Prevents food from spoiling ✅
b) Changes food color
c) Makes food taste bad
d) Removes vitamins

13. Which chemical is used in food preservation?
a) Sodium chloride ✅
b) Ammonium nitrate
c) Sulfuric acid
d) Hydrogen peroxide

14. What is the role of chemistry in medicine?
a) Helps develop drugs ✅
b) Cures diseases
c) Both A and B ✅
d) None of the above

15. Which of these is an example of a chemical used in cosmetics?
a) Sulfur ✅
b) Sodium chloride
c) Carbon dioxide
d) Ammonium sulfate

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Common Chemicals and Their Uses

16. Which gas is used in the making of POP (Plaster of Paris)?
a) Oxygen
b) Carbon dioxide
c) Sulfur dioxide
d) None of the above ✅

17. Which material is used to make glass?
a) Silica (SiO₂) ✅
b) Sodium chloride
c) Calcium carbonate
d) Hydrochloric acid

18. Which of the following is used in making soap?
a) Fatty acids and sodium hydroxide ✅
b) Carbon dioxide and water
c) Hydrogen and nitrogen
d) Calcium carbonate

19. What is the main chemical used in plastics?
a) Polymers ✅
b) Ammonium sulfate
c) Sodium chloride
d) Copper sulfate

20. Cement is made from:
a) Limestone ✅
b) Copper
c) Plastic
d) Sugar

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Chemistry in Agriculture

21. Which chemical is commonly used in fertilizers?
a) Urea ✅
b) Sodium chloride
c) Ammonium sulfate
d) Carbon dioxide

22. What is the role of pesticides in agriculture?
a) To protect plants from pests ✅
b) To provide nutrients
c) To make plants taller
d) To improve soil quality

23. Which of the following is a natural fertilizer?
a) Compost ✅
b) Ammonium nitrate
c) Urea
d) Superphosphate

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More Applications of Chemistry

24. Which chemical is used in making paints and enamels?
a) Titanium dioxide ✅
b) Sodium chloride
c) Calcium carbonate
d) Hydrochloric acid

25. What is the main ingredient in soap making?
a) Sodium hydroxide ✅
b) Potassium nitrate
c) Hydrochloric acid
d) Ammonium chloride

26. What is silicon commonly used in?
a) Electronics ✅
b) Medicine
c) Agriculture
d) Cement

27. Which of the following is an artificial sweetener?
a) Aspartame ✅
b) Glucose
c) Fructose
d) Sucrose

28. What is the role of preservatives in food?
a) To prevent spoilage ✅
b) To make food tastier
c) To remove bacteria
d) To add color

29. Which chemical is used in detergents?
a) Sodium lauryl sulfate ✅
b) Calcium chloride
c) Ammonium nitrate
d) Potassium hydroxide

30. What is the main ingredient in glass production?
a) Sand (Silica) ✅
b) Copper
c) Plastic
d) Wood

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Chemistry in Daily Life (Continued)

31. Which gas is commonly used in soft drinks?
a) Oxygen
b) Carbon dioxide ✅
c) Hydrogen
d) Nitrogen

32. What chemical is commonly used in matchsticks?
a) Phosphorus ✅
b) Sodium chloride
c) Calcium carbonate
d) Potassium nitrate

33. The chemical used to disinfect swimming pools is:
a) Chlorine ✅
b) Oxygen
c) Hydrogen
d) Sulfur

34. What is the main component of common salt?
a) Sodium chloride ✅
b) Potassium chloride
c) Calcium sulfate
d) Magnesium oxide

35. The gas used in balloons to make them float is:
a) Helium ✅
b) Oxygen
c) Hydrogen
d) Nitrogen

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Food and Chemistry

36. Which of the following is a preservative used in pickles?
a) Vinegar ✅
b) Sugar
c) Salt
d) Both a and c ✅

37. What vitamin is present in citrus fruits?
a) Vitamin A
b) Vitamin B
c) Vitamin C ✅
d) Vitamin D

38. Which mineral is essential for strong bones and teeth?
a) Iron
b) Calcium ✅
c) Sodium
d) Magnesium

39. What is the main nutrient in milk?
a) Protein ✅
b) Carbohydrates
c) Fats
d) Vitamins

40. The process of heating milk to kill germs is called:
a) Fermentation
b) Pasteurization ✅
c) Condensation
d) Sublimation

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Chemistry in Agriculture

41. Which gas is essential for plant growth?
a) Oxygen
b) Carbon dioxide ✅
c) Nitrogen
d) Hydrogen

42. The main nutrient present in fertilizers is:
a) Sodium
b) Potassium ✅
c) Magnesium
d) Sulfur

43. Which chemical is used to kill pests in farming?
a) Pesticides ✅
b) Fertilizers
c) Minerals
d) Vitamins

44. What is organic farming?
a) Farming without chemical fertilizers and pesticides ✅
b) Farming using synthetic chemicals
c) Farming in water
d) Farming with artificial seeds

45. Which gas is essential for photosynthesis?
a) Carbon dioxide ✅
b) Oxygen
c) Nitrogen
d) Helium

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Chemistry in Industry

46. Which chemical is used in cement production?
a) Limestone ✅
b) Sodium chloride
c) Copper sulfate
d) Ammonium nitrate

47. What is the main chemical used in glassmaking?
a) Silica (SiO₂) ✅
b) Iron oxide
c) Copper sulfate
d) Calcium carbonate

48. Which chemical is used in making plastic?
a) Polymers ✅
b) Hydrochloric acid
c) Nitrogen gas
d) Magnesium oxide

49. What is the main ingredient in detergents?
a) Sodium lauryl sulfate ✅
b) Calcium chloride
c) Magnesium carbonate
d) Potassium nitrate

50. Which gas is commonly used in fire extinguishers?
a) Carbon dioxide ✅
b) Oxygen
c) Hydrogen
d) Nitrogen

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Famous Scientists and Their Contributions

51. Who discovered radioactivity?
a) Antoine Lavoisier
b) Marie Curie ✅
c) John Dalton
d) Robert Boyle

52. Who gave the law of conservation of mass?
a) Antoine Lavoisier ✅
b) John Dalton
c) Dmitri Mendeleev
d) Joseph Priestley

53. The periodic table was arranged by:
a) J.J. Thomson
b) Dmitri Mendeleev ✅
c) Robert Boyle
d) Marie Curie

54. The discovery of oxygen is credited to:
a) Joseph Priestley ✅
b) Antoine Lavoisier
c) John Dalton
d) Robert Boyle

55. Prafulla Chandra Ray was an Indian chemist known for:
a) Discovering mercurous nitrite ✅
b) Developing the atomic theory
c) Creating the periodic table
d) Discovering helium

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Miscellaneous Chemistry Applications

56. Which gas is used in refrigerators?
a) Ammonia ✅
b) Oxygen
c) Nitrogen
d) Hydrogen

57. Which chemical is used to make artificial sweeteners?
a) Aspartame ✅
b) Sodium chloride
c) Calcium carbonate
d) Magnesium sulfate

58. What is the main component of soaps?
a) Fatty acids and sodium hydroxide ✅
b) Carbon dioxide
c) Calcium chloride
d) Iron oxide

59. What chemical is used in making dyes?
a) Aniline ✅
b) Sodium hydroxide
c) Magnesium sulfate
d) Calcium carbonate

60. The chemical name for baking soda is:
a) Sodium bicarbonate ✅
b) Calcium carbonate
c) Sodium chloride
d) Magnesium sulfate

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61-80: Chemistry in Everyday Life

61. Which gas do plants release during photosynthesis?
a) Oxygen ✅
b) Carbon dioxide
c) Nitrogen
d) Hydrogen

62. What is the chemical name of table salt?
a) Sodium chloride ✅
b) Calcium carbonate
c) Potassium permanganate
d) Magnesium sulfate

63. The chemical used to make bleaching powder is:
a) Calcium hypochlorite ✅
b) Sodium chloride
c) Calcium carbonate
d) Potassium nitrate

64. What is the main ingredient in toothpaste?
a) Fluoride ✅
b) Sodium chloride
c) Ammonium nitrate
d) Copper sulfate

65. The chemical formula of water is:
a) H₂O ✅
b) CO₂
c) O₂
d) H₂SO₄

66. Which gas is used in electric bulbs?
a) Argon ✅
b) Oxygen
c) Hydrogen
d) Nitrogen

67. Which metal is used in thermometers?
a) Mercury ✅
b) Iron
c) Silver
d) Copper

68. The chemical symbol for gold is:
a) Au ✅
b) Ag
c) Fe
d) Cu

69. Which gas is responsible for global warming?
a) Carbon dioxide ✅
b) Oxygen
c) Hydrogen
d) Helium

70. The pH value of pure water is:
a) 7 ✅
b) 5
c) 10
d) 14

71. Which of these is an acid?
a) Hydrochloric acid (HCl) ✅
b) Sodium hydroxide (NaOH)
c) Water (H₂O)
d) Oxygen (O₂)

72. Which of these is a base?
a) Sodium hydroxide (NaOH) ✅
b) Hydrochloric acid (HCl)
c) Carbon dioxide (CO₂)
d) Ammonia (NH₃)

73. Which chemical gives fruits their sour taste?
a) Citric acid ✅
b) Acetic acid
c) Hydrochloric acid
d) Sulfuric acid

74. The gas used in balloons and airships is:
a) Helium ✅
b) Oxygen
c) Hydrogen
d) Carbon dioxide

75. What is the formula of carbon dioxide?
a) CO₂ ✅
b) O₂
c) H₂O
d) NaCl

76. What is the main element in charcoal?
a) Carbon ✅
b) Hydrogen
c) Oxygen
d) Sulfur

77. What is dry ice?
a) Solid carbon dioxide ✅
b) Frozen water
c) Crushed ice
d) Sodium chloride

78. Which of the following is used in batteries?
a) Lithium ✅
b) Calcium
c) Sodium
d) Magnesium

79. Which chemical is present in washing soda?
a) Sodium carbonate (Na₂CO₃) ✅
b) Sodium chloride (NaCl)
c) Calcium carbonate (CaCO₃)
d) Potassium nitrate (KNO₃)

80. What is the pH scale used for?
a) To measure acidity or alkalinity ✅
b) To measure temperature
c) To measure weight
d) To measure volume

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81-100: Miscellaneous Chemistry Facts

81. What is the chemical name for vinegar?
a) Acetic acid ✅
b) Citric acid
c) Hydrochloric acid
d) Sulfuric acid

82. What is the chemical formula of ammonia?
a) NH₃ ✅
b) CO₂
c) O₂
d) H₂O

83. What type of chemical bond is present in water?
a) Covalent bond ✅
b) Ionic bond
c) Metallic bond
d) Hydrogen bond

84. Which gas is used to ripen fruits artificially?
a) Ethylene ✅
b) Oxygen
c) Carbon dioxide
d) Hydrogen

85. Which acid is present in the human stomach?
a) Hydrochloric acid (HCl) ✅
b) Acetic acid
c) Sulfuric acid
d) Nitric acid

86. The chemical formula of sulfuric acid is:
a) H₂SO₄ ✅
b) HCl
c) NaOH
d) CO₂

87. Which metal is used for making aircraft parts?
a) Aluminium ✅
b) Iron
c) Silver
d) Copper

88. The chemical formula of rust is:
a) Fe₂O₃ ✅
b) FeO
c) FeS
d) FeCO₃

89. What is the main chemical in chalk?
a) Calcium carbonate (CaCO₃) ✅
b) Sodium chloride
c) Potassium hydroxide
d) Magnesium oxide

90. Which gas is responsible for acid rain?
a) Sulfur dioxide (SO₂) ✅
b) Oxygen
c) Hydrogen
d) Nitrogen

91. What is the chemical name of quicklime?
a) Calcium oxide (CaO) ✅
b) Calcium carbonate
c) Sodium hydroxide
d) Potassium chloride

92. The main chemical in firecrackers is:
a) Potassium nitrate ✅
b) Sodium chloride
c) Magnesium sulfate
d) Calcium carbonate

93. What is the hardest natural substance on Earth?
a) Diamond ✅
b) Gold
c) Iron
d) Graphite

94. What is the chemical name of baking powder?
a) Sodium bicarbonate ✅
b) Calcium carbonate
c) Potassium chloride
d) Ammonium sulfate

95. The main gas in Earth's atmosphere is:
a) Nitrogen ✅
b) Oxygen
c) Carbon dioxide
d) Hydrogen

96. Which chemical is used in perfumes?
a) Esters ✅
b) Acids
c) Bases
d) Salts

97. Which chemical is used to clean water in swimming pools?
a) Chlorine ✅
b) Sodium
c) Carbon dioxide
d) Hydrogen peroxide

98. The chemical formula for hydrogen peroxide is:
a) H₂O₂ ✅
b) CO₂
c) H₂O
d) NH₃

99. Which gas is used in fluorescent lights?
a) Neon ✅
b) Oxygen
c) Hydrogen
d) Carbon dioxide

100. Which scientist discovered electrons?
a) J.J. Thomson ✅
b) John Dalton
c) Dmitri Mendeleev
d) Marie Curie