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Daily Pharma QuizpharmacyTopic wise MCQs

Alkane MCQs with Answers

Alkane

1. Which represents an alkane………
(a) C5H8
(b) C6H8
(c) C9H10
(d) C7H16
Ans. : d

2. The decreasing order of boiling points is ……….
(a) n-Pentane > iso-Pentane > neo-Pentane
(b) iso-Pentane > n-Pentane > neo-Pentane
(c) neo-Pentane > iso-Pentane > n-Pentane
(d) n-Pentane > neo-Pentane > iso-Pentane
Ans.: a

3. To prepare a pure sample of n-hexane using sodium metal as one reactant, the other reactant will be………
(a) n-propyl bromide
(b) Ethyl bromide and n-butyl bromide
(c) Ethyl chloride and n-butyl chloride
(d) Methyl bromide and n -pentyl chloride
Ans.: a

4. In the preparation of Grignard reagent from haloalkane, the metal
(a) Mg
(b) Zn
(c) Li
(d) K
Ans.: a

5. Sodium acetate can be converted to ethane by……….
(a) Heating with LiAlH4
(b) Electrolysing its aqueous solution
(c) Heating with sodalime
(d) Heating with calcium acetate
Ans.: b

6. Which of the following compounds is used in antiknock compositions to prevent the deposition of oxides of lead on spark plug, combustion chamber and exhaust pipe…….

(a) Glycerol
(b) Glycol
(c) 1, 2-dibromoethane
(d) Benzene
Ans.: c

7. Which of petroleum corresponds to kerosene oil………
(a) C15-C18
(b) C10 – C12
(c) C5 – C9
(d) C1 –C9
Ans.: b

8. In the reaction CH3- Br+ 2Na+ Br-CH3 , the product called ……..
(a) Wurtz reaction
(b) Aldol condensation
(c) Perkin’s reaction
(d) Levit reaction
Ans.: a

9. Iodoethane reacts with sodium in the presence of dry ether. The product is……..
(a) Pentane
(b) Propane
(c) Butene
(d) Butane
Ans.: d

10. Which of the following is oxidised by KMnO4
(a) Methane
(b) Pentane
(c) Isobutane
(d) Neopentane
Ans.: c

11. The most volatile compound is……….
(a) 2, 2-dimethyl propane
(b) 2-methyl butane
(c) Isobutane
(d) n-pentane
Ans.: a

12. In Wurtz reaction, the reagent used is………..
(a) Na
(b) liquid NH3Na
(c) ether dry Na
(d) alcohol dry Na
Ans.: c

13. Which of the following has highest octane number…………
(a) n-hexane
(b) n-heptane
(c) n-pentane
(d) 2, 2, 4-trimethyl pentane
Ans.: d

14. What is freon-12…….
(a) Pesticide
(b) Refrigerant
(c) Solvent
(d) Lubricant
Ans.: b

15. The petrol having octane number 80 has…………
(a) 20% normal heptane + 80% iso-octane
(b) 80% normal heptane + 20% iso-octane
(c) 20% normal heptane + 80% normal octane
(d) 80% normal heptane + 20% normal octane
Ans.: a

16. The shape of methane molecule is………..
(a) Linear
(b) Trigonal planar
(c) Square planar
(d) Tetrahedral
Ans.: d

17. . Which of the following shows only one brominated compound…………
(a) Butene-2
(b) 2, 2-dimethylpropane
(c) Butyne-1
(d) Butanol-3
Ans.: b

18. Kerosene is used as fuel because it is………….
(a) Less volatile
(b) More volatile
(c) Cheap
(d) Abundantly available
Ans.: b

19. Which of the following statements is not true for ethane………….
(a) It can be chlorinated with chlorine
(b) It can be catalytically hydrogenated
(c) When oxidised produces CO2 and H2O
(d) It is a homologue of iso-butane

Ans.: b

20. Petroleum refining is ……………
(a) Distillation of petroleum to get different fractions
(b) Obtaining aromatic compounds from aliphatic compounds present in petroleum
(c) Cracking of petroleum to get gaseous hydrocarbons
(d) Purification of petroleum
Ans.: a

21. The chemical added to leaded petrol to prevent the deposition of lead in the combustion chamber is……
(a) Iso-octane
(b) Ethylene dibromide
(c) Tetraethyl lead
(d) Mercaptan
(e) n-Heptane
Ans.: b

22. In the commercial gasolines, the type of hydrocarbons which are more desirable is………..
(a) Branched hydrocarbon
(b) Straight-chain hydrocarbon
(c) Linear unsaturated hydrocarbon
(d) Toluene
Ans.: a

23. Which of the following is not formed by the reaction of Cl2 on CH4 in sunlight……….
(a) CHCl3
(b) CH3Cl
(c) CH3CH3
(d) CH3CH2CH3
Ans.: d

24. Which of the following has the highest boiling point………..
(a) Neopentane
(b) n-butane
(c) n-heptane
(d) Isobutane
Ans.: c

25. Which gives CH4 when treated with water……..
(a) Silicon carbide
(b) Calcium carbide
(c) Aluminium carbide
(d) Iron carbide
Ans.: c

26. Which of the following does not react with PCl5
(a) CH3OH
(b) CH3COOH
(c) CH3CHO
(d) C2H6

Ans.: d

27. Which of the following compounds is insoluble even in hot concentrated H2SO4………
(a) Ethylene
(b) Benzene
(c) Hexane
(d) Aniline
Ans.: c

28. A reaction between methyl magnesium bromide and ethyl alcohol gives……….
(a) Methane
(b) Ethane
(c) Propane
(d) Butane
Ans.: a

29. Methane and ethane both can be obtained in single step from …………
(a) CH3 I
(b) C2H5I
(c) CH3OH
(d) C2H5OH
Ans.: a

30. Paraffin wax is………..
(a) Ester
(b) Alcohol
(c) Unsaturated hydrocarbon
(d) Saturated Hydrocrabon
Ans.: d

31. The number of possible enantiomeric pairs that can be produced during monochlorination of 2- methylbutane is ……..
(a) 2
(b) 3
(c) 4
(d) 1
Ans.: a

32. Petroleum consists mainly of…………
(a) Aliphatic hydrocarbons
(b) Aromatic hydrocarbons
(c) Aliphatic alcohols
(d) None of these
Ans.: a

33. Petroleum ether can be used as……….
(a) Solvent for fat, oil, varnish and rubber
(b) As a fuel
(c) Both (a) and (b)
(d) None of these
Ans.: a

34. Which of the following are produced from coaltar………..
(a) Synthetic dyes
(b) Drugs
(c) Perfumes
(d) All the three
Ans.: d

35. In alkanes, the bond angle is……..
(a) 109.5 o
(b) 109 o

(c) 120 o
(d) 180 o
Ans.: a

36. In the preparation of alkanes; a concentrated aqueous solution of sodium or potassium salts of saturated carboxylic acid are subjected to………
(a) Hydrolysis
(b) Oxidation
(c) Hydrogenation
(d) Electrolysis
Ans.: d

37. Halogenation of alkanes is an example of………..
(a) Electrophilic substitution
(b) Nucleophilic substitution
(c) Free-radical substitution
(d) Oxidation
Ans.: c

38. Propionic acid is subjected to reduction with hydroiodic acid in the presence of a little P, the product formed is…………
(a) Ethane
(b) Propane
(c) Butane
(d) None of these
Ans.: b

39. When ethyl iodide and propyl iodide react with Na in the presence of ether, they form………
(a) One alkane
(b) Two alkanes
(c) Four alkanes
(d) Three alkanes
Ans.: d

40. The alkane that yields two isomeric monobromo derivatives is……………
(a) Neopentane
(b) Ethane
(c) Methane
(d) Propane
Ans.: d

41. Kerosene is a mixture of………….
(a) Alkanes
(b) Aromatic compounds
(c) Alcohols
(d) Aliphatic acids
Ans.: b

42. When petroleum is heated the vapours contain mainly………….
(a) Kerosene
(b) Petroleum ether
(c) Diesel
(d) Machine oil
Ans.: d

43. Iso-octane is mixed to the petrol………….
(a) To precipitate inorganic substances
(b) To prevent freezing of petrol
(c) To increase boiling point of petrol
(d) As an antiknock
Ans.: d

44. Cyclohexane, a hydrocarbon floats on water because…………
(a) It is immiscible with water
(b) Its density is low as compared to water
(c) It is non-polar substance
(d) It is immiscible and lighter than water
Ans.: a

45. Natural gas contains mainly………….
(a) Methane
(b) n-butane
(c) n-octane
(e) Mixture of octane
Ans.: d

46. Which compound is not inflammable………..
(a) CCl4
(b) C2H5OH
(c) CH4
(d) C6H6
Ans.: a

47. Propane is obtained from propene, by which of the following methods……….
(a) Wurtz reaction
(b) Dehydrogenation
(c) Frankland reaction
(d) Catalytic hydrogenation
Ans.: a

48. The organic compound used as antiknock agent in petroleum is…………

(a) (C2H5)4 Pb
(b) TNT
(c) CH3 MgBr
(d) (C2H5)2Hg
Ans.:

49. In catalytic reduction of hydrocarbons which catalyst is mostly used…………
(a) Pt /Ni
(b) Pd
(c) SiO2
(d) Misch Metal
Ans.: c

50. Ethylene reacts with bromine to form ………….
(a) Br CH2 CH3
(b) CH3CBr3
(c) Br CH2CH2Br
(d) CHBr3
Ans.: a