NCERT Book Class 10th SCIENCE MCQ
Chapter 4 : Carbon and its Compounds
Multiple-Choice Questions (MCQs) with Answers
1. What is the atomic number of carbon?
a) 6
b) 12
c) 14
d) 16
Answer: a) 6
2. What is the electronic configuration of carbon?
a) 2,4
b) 2,8
c) 2,8,4
d) 2,6
Answer: a) 2,4
3. Which property of carbon allows it to form a large number of compounds?
a) Isomerism
b) Catenation
c) Oxidation
d) Reduction
Answer: b) Catenation
4. Which of the following is not an allotrope of carbon?
a) Diamond
b) Graphite
c) Ozone
d) Fullerene
Answer: c) Ozone
5. Why is graphite a good conductor of electricity?
a) It has free electrons
b) It is soft
c) It has a three-dimensional structure
d) It is colorless
Answer: a) It has free electrons
6. What is the molecular formula of ethane?
a) CH₄
b) C₂H₄
c) C₂H₆
d) C₃H₈
Answer: c) C₂H₆
7. What type of bond is present in alkenes?
a) Single bond
b) Double bond
c) Triple bond
d) Ionic bond
Answer: b) Double bond
8. To which class of hydrocarbons does C₃H₆ belong?
a) Alkane
b) Alkene
c) Alkyne
d) Aromatic
Answer: b) Alkene
9. Which of the following compounds is unsaturated?
a) Methane
b) Ethane
c) Ethylene
d) Butane
Answer: c) Ethylene
10. What happens to the color of bromine water when it reacts with an unsaturated hydrocarbon?
a) Yellow
b) Purple
c) Colorless
d) Green
Answer: c) Colorless
11. Which functional group is present in alcohols?
a) -COOH
b) -OH
c) -CHO
d) -CO-
Answer: b) -OH
12. What is the formula of ethanol?
a) CH₃OH
b) C₂H₅OH
c) C₃H₇OH
d) C₄H₉OH
Answer: b) C₂H₅OH
13. Which of the following is a carboxylic acid?
a) CH₃OH
b) CH₃COOH
c) CH₃CHO
d) CH₃COCH₃
Answer: b) CH₃COOH
14. What is formed in an esterification reaction?
a) Alcohol
b) Ester
c) Ether
d) Ketone
Answer: b) Ester
15. What is the process of soap-making called?
a) Esterification
b) Saponification
c) Reduction
d) Oxidation
Answer: b) Saponification
16. CBSE 2020: Write two properties of carbon that enable it to form a large number of compounds.
Answer: Catenation and tetravalency
17. MP Board 2019: The formula of propane is:
a) C₃H₆
b) C₃H₈
c) C₄H₁₀
d) C₂H₆
Answer: b) C₃H₈
18. Bihar Board 2021: What is formed when ethanol is heated with concentrated H₂SO₄?
a) Ethene
b) Methane
c) Ethane
d) Propane
Answer: a) Ethene
19. UP Board 2018: The ionic part of a soap molecule is called:
a) Hydrophobic
b) Hydrophilic
c) Micelle
d) Glycerol
Answer: b) Hydrophilic
20. CBSE 2022: Which of the following is an aldehyde?
a) CH₃COOH
b) CH₃CHO
c) CH₃OH
d) CH₃COCH₃
Answer: b) CH₃CHO
21. The hydrocarbon tail in a soap molecule is:
a) Water-repelling (Hydrophobic)
b) Water-attracting (Hydrophilic)
c) Neutral
d) Acidic
Answer: a) Water-repelling (Hydrophobic)
22. Ethanol is not used in:
a) Fuel
b) Medicines
c) Making plastics
d) Making alcoholic beverages
Answer: c) Making plastics
23. What happens in the micelle formation process?
a) Oil molecules dissolve in water
b) Soap molecules form a colloid in water
c) Glycerol is formed
d) Acid and base react
Answer: b) Soap molecules form a colloid in water
24. What is obtained when ethanoic acid reacts with ethanol in the presence of concentrated H₂SO₄?
a) Ethyl ethanoate
b) Methane
c) Acetone
d) Glucose
Answer: a) Ethyl ethanoate
25. The reason carbon is essential for living organisms is:
a) It participates in photosynthesis
b) It is the fundamental element of all organic compounds
c) It generates energy
d) It is water-soluble
Answer: b) It is the fundamental element of all organic compounds
26. What is Isomerism?
a) Same molecular formula but different structure
b) Same physical properties
c) Same chemical properties
d) Same functional group
Answer: a) Same molecular formula but different structure
27. How many structural isomers does Butane (C₄H₁₀) have?
a) 1
b) 2
c) 3
d) 4
Answer: b) 2 (n-butane and isobutane)
28. Which compound is NOT an isomer of Ethanoic Acid?
a) Methyl formate (HCOOCH₃)
b) Propanoic acid (C₂H₅COOH)
c) Ethyl formate (HCOOC₂H₅)
d) Dimethyl ether (CH₃OCH₃)
Answer: d) Dimethyl ether (CH₃OCH₃)
29. What type of isomerism is shown by Ethanol and Dimethyl ether?
a) Chain isomerism
b) Functional group isomerism
c) Position isomerism
d) Tautomerism
Answer: b) Functional group isomerism
30. Which compound is NOT an isomer of C₃H₆O?
a) Propanal (CH₃CH₂CHO)
b) Acetone (CH₃COCH₃)
c) Propanone (CH₃CH₂COH)
d) Methyl acetate (CH₃COOCH₃)
Answer: d) Methyl acetate (CH₃COOCH₃)
31. What is obtained when Ethanol is oxidized?
a) Ethanoic acid
b) Methane
c) Ethene
d) Carbon dioxide
Answer: a) Ethanoic acid
32. Which reaction is an example of Esterification?
a) CH₃COOH + C₂H₅OH → CH₃COOC₂H₅ + H₂O
b) CH₄ + 2O₂ → CO₂ + 2H₂O
c) C₂H₄ + Br₂ → C₂H₄Br₂
d) 2H₂ + O₂ → 2H₂O
Answer: a) CH₃COOH + C₂H₅OH → CH₃COOC₂H₅ + H₂O
33. Which reaction occurs in soap-making?
a) Fat + NaOH
b) Fat + HCl
c) Fat + NaCl
d) Fat + CH₃COOH
Answer: a) Fat + NaOH
34. What is formed when Ethene reacts with Bromine water?
a) 1,2-Dibromoethane
b) Ethane
c) Ethyne
d) Methane
Answer: a) 1,2-Dibromoethane
35. Which reaction is an example of an Addition reaction?
a) CH₄ + Cl₂ → CH₃Cl + HCl
b) C₂H₄ + H₂ → C₂H₆
c) C₂H₅OH → C₂H₄ + H₂O
d) CH₃COOH + NaOH → CH₃COONa + H₂O
Answer: b) C₂H₄ + H₂ → C₂H₆
36. Chloroform (CHCl₃) is used as:
a) Fuel
b) Solvent and anesthetic
c) Soap-making
d) Plastic production
Answer: b) Solvent and anesthetic
37. Methanol (Methyl alcohol) is used in:
a) Alcoholic beverages
b) Fuel and solvent
c) Food preservatives
d) Soap-making
Answer: b) Fuel and solvent
38. Acetone (CH₃COCH₃) is used in:
a) Paint removal
b) Medicines
c) Plastic production
d) All of the above
Answer: d) All of the above
39. Formalin is an aqueous solution of:
a) Methanol
b) Ethanol
c) Formaldehyde
d) Acetone
Answer: c) Formaldehyde
40. Which compound is found in vinegar?
a) Ethanoic acid
b) Formic acid
c) Citric acid
d) Lactic acid
Answer: a) Ethanoic acid
41. Which gas is emitted by burning fossil fuels?
a) Oxygen
b) Nitrogen
c) Carbon dioxide
d) Hydrogen
Answer: c) Carbon dioxide
42. Which gas is primarily responsible for the Greenhouse Effect?
a) Oxygen
b) Nitrogen
c) Carbon dioxide
d) Hydrogen
Answer: c) Carbon dioxide
43. Polythene is a polymer of:
a) Ethane
b) Ethene
c) Propane
d) Butane
Answer: b) Ethene
44. Which material is NOT biodegradable?
a) Paper
b) Plastic
c) Wood
d) Cloth
Answer: b) Plastic
45. Which compound damages the Ozone layer?
a) CH₄
b) CFC
c) CO₂
d) H₂O
Answer: b) CFC
46. How many covalent bonds are in an Ethane (C₂H₆) molecule?
a) 6
b) 7
c) 8
d) 9
Answer: b) 7 (6 C-H + 1 C-C)
47. If the mass of one carbon atom is 12u, what is the mass of 3 moles of carbon?
a) 12g
b) 24g
c) 36g
d) 48g
Answer: c) 36g
48. What is the molecular mass of Ethanol (C₂H₅OH)?
(Given: C=12u, H=1u, O=16u)
a) 46u
b) 45u
c) 44u
d) 43u
Answer: a) 46u
49. How many CO₂ molecules are produced in the complete combustion of Propane (C₃H₈)?
a) 1
b) 2
c) 3
d) 4
Answer: c) 3
50. What is the percentage of oxygen in Ethanoic Acid (CH₃COOH)?
(Given: C=12u, H=1u, O=16u)
a) 26.6%
b) 53.3%
c) 40%
d) 60%
Answer: b) 53.3%