CBSE Class 11 Chemistry Hydrocarbons Worksheet Set A

Question. Attacking or reactive or electrophilic species in nitration of benzene is or In the nitration of benzene with concentrated 3 2 4 HNO and H SO the attack on ring is made by:
a. 2 NO₂⁻
b. 2 NO₂⁺
c. 3 NO₃⁻
d. 2 NO₂
Answer : B

Question. Pyridine is less basic than triethylamine because:
a. Pyridine has aromatic character
b. Nitrogen in pyridine is sp2 hybridized
c. Pyridine is a cyclic system
d. In pyridine, lone pair of nitrogen is delocalized
Answer : D

Question. Which of the following has highest octane number?
a. n-hexane
b. n-heptane
c. n-pentane
d. 2, 2, 4-trimethyl pentane
Answer : D

Question. Order of reactivity of C₂H₆ , C₂H₄ and C₂H₂ is
a. C₂H₆ > C₂H₄ > C₂H₂
b. C₂H₂ > C₂H₆ > C₂H₄
c. C₂H₂ > C₂H₄ > C₂H₆
d. All are equally reactive
Answer : C

Question. 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
Answer : A

Question. Which of the following is not used in Friedel-crafts reaction?
a. Phenyl acetanilide
b. Bromobenzene
c. Benzene
d. Chlorobenzene
Answer : A

Question. In Wurtz reaction, the reagent used is:
a. Na
b. Na liquid NH₃
c. Na dry ether
d. Na dry alcohol
Answer : C

Question. 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
Answer : A

Question. Which of the following are produced from coaltar?
a. Synthetic dyes
b. Drugs
c. Perfumes
d. All the three
Answer : D

Question. In alkanes, the bond angle is:
a. 109.5°
b. 109°
c. 120°
d. 180°
Answer : A

Question. Which of the following is oxidised by KMnO₄ ?
a. Methane
b. Pentane
c. Isobutane
d. Neopentane
Answer : C

Question. 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
Answer : B

Question. Which of the following oil is obtained from benzene after fractional distillation of coal tar?
a. Light oil
b. Heavy oil
c. Middle oil
d. Anthracene oil
Answer : A

Question. Coaltar is main source of:
a. Aromatic compounds
b. Aliphatic compounds
c. Cycloalkanes
d. Heterocyclic compounds
Answer : A

Question. 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
Answer : A

Question. Gasoline is obtained from crude petroleum oil by its:
a. Fractional distillation
b. Vacuum distillation
c. Steam distillation
d. Pyrolysis
Answer : A

Question. Carbon black, which is used in making printer's ink, is obtained by decomposition of?
a. Acetylene
b. Benzene
c. Carbon tetrachloride
d. Methane
Answer : D

Question. Which is the best antiknock compound or Which one of the following substances is used as an antiknock compound?
a. Lead tetrachloride
b. Lead acetate
c. Zinc ethyl
d. Tetraethyl lead (TEL)
Answer : D

Question. 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
Answer : D

Question. Natural gas contains mainly:
a. Methane
b. n-butane
c. n-octane
d. Mixture of octane
Answer : A

Question. B.P. of branched chain alkanes as compared to straight chain alkanes are:
a. Lower
b. Equal
c. Higher
d. Independent of the chain
Answer : A

Question. In catalytic reduction of hydrocarbons which catalyst is mostly used?
a. Pt /Ni
b. Pd
c. SiO₂
d. Misch Metal
Answer : A

Question. Most of the hydrocarbons from petroleum are obtained by:
a. Fractional distillation
b. Fractional crystallization
c. Vaporization
d. Polymerization
Answer : A

Question. As the number of carbon atoms in a chain increases the boiling point of alkanes:
a. Increases
b. Decreases
c. Remains same
d. May increase or decrease
Answer : A

Question. Which of the following will have least hindered rotation about carbon-carbon bond?
a. Ethane
b. Ethylene
c. Acetylene
d. Hexachloroethane
Answer : A

Question. Which of the following occurs easily in ethylene?
a. Addition
b. Substitution
c. Elimination
d. Rearrangement
Answer : A

Question. Conjugate double bond is present in
a. Propylene
b. Butadiene
c. Isobutylene
d. Butylene
Answer : B

Question. The homologue of ethyne is:
a. C₂H₄
b. C₂H₄
c. C₃H₈
d. C₃H₄
Answer : D

Question. Which one of the following has the minimum boiling point?
a. 1-Butene
b. 1-Butyne
c. n-Butane
d. Isobutane
Answer : D

Question. In paraffins, with the increasing molecular weight, it is found that?
a. Freezing point decreases
b. Boiling point decreases
c. Boiling point increases
d. Vapour pressure decreases
Answer : C

Question. A gas decolourised KMnO₄ solution but gives no precipitate with ammoniacal cuprous chloride is or Which of the following gases does not give a precipitate with ammoniacal solution of silver nitrate but decolourizes KMnO₄ (neutral or slightly alkaline)
a. Ethane
b. Methane
c. Ethene
d. Acetylene
Answer : C

Question. The distinguishing test for triple bond containing acidic hydrogen is:
a. Ag(NH₃)₂⁺
b. Br₂ in CCl₄
c. Alkaline KMnO₄
d. AlCl₃
Answer : A

Question. The reaction of toluene with chlorine in presence of ferric chloride gives predominantly:
a. Benzoyl chloride
b. m-chlorotoluene
c. Benzyl chloride
d. o- and p-chlorotoluenes
Answer : D

Question. Which of the following is the most stable?
a. 1-butene
b. 2-butene
c. 1-pentene
d. 2-pentene
Answer : D

Question. A reagent used to test for unsaturation of allkene is:
a. conc. H₂SO₄
b. Ammonical Cu₂Cl₂
c. Ammonical AgNO₃
d. Solution of Br₂ in CCl₄
Answer : D

Question. Which of these does not follow Anti-Markownikoff's rule?
a. 2-butene
b. 1-butene
c. 2-pentene
d. 2-hexene
Answer : A

Question. A mixture of ethane, ethene and ethyne is passed through ammoniacal 3 AgNO solution. The gases which remain unreacted are:
a. Ethane and ethene
b. Ethane and ethyne
c. Ethene and ethyne
d. Ethane only
Answer : A