CBSE Class 11 Chemistry Hydrocarbons MCQs Set D

Question. Ethylene reacts with 1 % alkaline KMnO₄ to form
(a) oxalic acid
(b) ethylene glycol
(c) ethyl alcohol
(d) HCHO   
Answer: b 

Question. When C₂H₂, CH₄ and C₂H₄ passes through a test tube which have ammoniacal Cu₂Cl₂, find out which gas comes out unaffected from test tube ?
(a) C₂H₂ and CH₄
(b) C₂H₂ and C₂H₄
(c) C₂H₂ and CH₄
(d) C₂H₂         
Answer: c 

Question. Ethylene can be converted into alcohol by treatment with
(a) aq KOH 
(b) dil. H₂SO⁴
(c) moist silver oxide
(d) Zn/HCI 
Answer: b   

Question. When acetylene is passed through dil. H₂SO₄ in presence of HgSO₄ , the compound fo1med is 
(a) ether
(b) acetaldehyde
(c) acetic acid
(d) ketone   
Answer: b

Question. According to Markownikoffs rule, what will be the major product of reaction,
CH₂= CH—CH₃ →^HBr ?
              Br
              l
(a) CH3—CH—CH3
(b) Br—CH₂—CH₂—CH₃
(c) CH₂= CH—CH₂Br
(d) CH₂=C=CH₂   
Answer: a

Question. Propyne on passing through red hot copper tube forms
(a) benzene
(b) toluene 
(c) mesitylene
(d) None of these   
Answer: c 

Question. Mustard gas is a
(a) oil gas
(b) poisonous gas
(c) fuel gas
(d) life gas   
Answer: b

Question. Propyne on ozonolysis gives 
(a) CH₃COOH + HCOOH
(b) CH₃COOH + HCHO
(c) CH₃CHO + HCHO
(d) CH₃CHO + HCOOH     
Answer: a

 Question. 2-hexyne gives trans-2-hexene on treatment with
(a) Pt/H₂
(b) Li/NH₃
(c) Pd/BaSO₄
(d) LiAlH₄       
Answer: b

Question. Which of the following is present in natw-al gas ?
(a) n-butane
(b) Ethane 
(c) Methane
(d) Propane     
Answer: c 

Question. Acetylene and HCHO react in presence of copper acetylide catalyst to form 
(a) 1-butyne-1, 4-diol
(b) 2-butyne-1, 2-diol
(c) 2-butyne-1 , 4-diol
(d) None of these     
Answer: c 

Question. Which one of the following compounds will react with methyl magnesium bromide?
(a) CH₃CH₂CH₂CH₂CH₃
(b) CH₃CH = CH—CH= CH2
(c) CH₃ —C = C—CH₂CH₃
(d) CH₃CH₂CH₂C = CH     
Answer: d

Question. Which of the following is correct order according to boiling point? 
(a) n-pentane < n-hexane < 2, 3-dimethyl butane
(b) n-pentane < 2, 3-dirnethyl butane< n-hexane
(c) 2, 3-din1ethyl butane< n-hexane < n-pentane
(d) n-hexane < 2, 3-dirnethyl butane< n-pentane   
Answer: b 

Question. The major organic compound formed by the reaction of 1, 1, 1- trichloroethane with silver powder is
(a) acetylene
(b) ethene
(c) 2-butyne
(d) 2-butene     
Answer: c 

Question. An alkene on reductive ozonolysis gives 2-molecules of CH₂ (CHO)₂ . The alkene is
(a) 2, 4-hexadiene
(b) 1, 3-cyclohexadiene
(c) 1, 4-cyclohexadiene
(d) 1-methyl- 1, 3-cyclopentadiene
(e) 1, 2-dirnethyl cyclopropene   
Answer: c 

Question. In the reaction sequence, Products will be
CH₃CH=CH₂    →^(i)O₃      Products will be
                        ^{(ii) H2O/Zn}
(a) CH₃ COCH₃ 
(b) CH₃ COCH₂OH
(c) CH₃ COOH + HCOOH
(d) CH₃ CHO + HCHO      
Answer: d 

Question. A compoundX on ozonolysis followed by reduction gives an aldehyde C₂H₄O and 2-butanone. Compound Xis
(a) 3-methyl pentene-2
(b) 3-methyl pentene-3
(c) 3-methyl hexene-3
(d) 3-ethyl pentene-3   
Answer: a 

Question. Which of the following alkenes gives an acetaldehyde on ozonolysis ?
(a) Ethene
(b) Propene
(c) 1 -butene
(d) 2-butene   
Answer: d

Question. What is the product formed when acetylene reacts with hypochlorous acid ? 
(a) CH₃COCI
(b) ClCH₂CHO
(c) Cl₂CHCHO
(d) ClCH₂COOH   
Answer: c

Question. Which compound does not give precipitate with anlflloniacal silver nitrate solution? 
(a) C₂H₅—C= CH
(b) CH₃—C=C—CH₃ 
              CH₃
              l
(c) CH₃—CH—C=CH
(d) Ph—CH₂—C=CH     
Answer: b

Question. The Markownikoff’s rule is the best applicable to the reaction between 
(a) C₂H₄ + HCI
(b) C₃H₆ + Br₂
(c) C₃H₆ + HBr
(d) C₃H₈ + Cl₂
(e) C₂H₄ + I₂     
Answer: c

Question. Which branched chain isomer of the hydrocarbon with molecular mass 72u gives only one isomer of mono substituted alkyl halide? 
(a) Te1tiarybutyl chloride
(b) Neo-pentane
(c) ]so-hexane
(d) Neo-hexane   
Answer: b

Question. Tetraethyl lead is a
(a) solvent
(b) petroleum additive
(c) oxidising agent
(d) fire extinguisher 
Answer: b

Question. In laboratory burners, we use 
(a) producer gas
(b) oil gas
(c) gobar gas
(d) coal gas   
Answer: b

Question. Which of the following is the predominant product in the reaction of HO Br with propene? 
(a) 2-bromo-1-propanol
(b) 3-bromo-1-propanol
(c) 2-bromo-2-propanol
(d) l-bromo-2-propanol
Answer: d 

Question. In the following reaction,
C₂H₂       →^H₂O     X ⇌ CH₃CHO.
           ^{HgSO₄/H₂SO₄}
What is X ? 
(a) CH₃CH₂OH
(b) CH₃ — O — CH₃
(c) CH₃CH₂CHO
(d) CH₂ = CHOH     
Answer: d 

Question. Which of the following increases the octane number ?
(a) Branching of chain
(b) Absence of double and triple bond
(c) Non-cyclic alkanes
(d) None of the above 
Answer: a

Question. 2-methylbutane on reacting with bromine in the presence of sunlight gives mainly 
(a) l-bromo-3-methylbutane
(b) 2-bromo-3-methylbutane
(c) 2-bromo-2-methylbutane
(d) l-bromo-2-methylbutane 
Answer: c 

Question. Which of the following is correct order according to boiling point? 
(a) n-pentane < n-hexane < 2, 3-dimethyl butane
(b) n-pentane < 2, 3-dirnethyl butane< n-hexane
(c) 2, 3-din1ethyl butane< n-hexane < n-pentane
(d) n-hexane < 2, 3-dirnethyl butane< n-pentane   
Answer: b 

Question. Which one of the following gives, on ozonolysis, both aldehydes and ketones ? 
(a) Me₂C==CHMe
(b) Me₂C=CMe2
(c) MeCH₂— C(Me) = CMe₂
(d) MeCH(Me)—CH = CHMe   
Answer: b

Question. One mole of a symmetrical alkene on ozonolysis gives two moles of an aldehyde having a molecular mass of 44 u. The alkene is 
(a) propene
(b) I-butene
(c) 2-butene
(d) ethene   
Answer: c 

Question. Which of the following fraction of coaltar distillation is obtained at 270°-360°C?
(a) Light oil
(b) Middle oil
(c) Green oil
(d) Heavy oil   
Answer: c

Question. Cetane is a compound which has very good ignition property. Chemically it is
(a) CH₃ (CH₂ )₁₄ CH₃
(b) (CH₃)₃ C(CH₂ )₁₁ CH₃
(c) C₁₇H₃₄
(d) None of the above   
Answer: a 

Question. The compound with highest boiling point 
(a) n-hexane
(b) n-pentane
(c) 2, 2-dimethylpropane
(d) 2-methylbutane 
Answer: a 

Question. When a mixture of methane and oxygen is passed through heated molybdenum oxide, the main product formed is
(a) methanoic acid
(b) ethanal 
(c) methanol
(d) methanal 
Answer: d

 Question. An alkene on vigorous oxidation with KMnO₄ gives only acetic acid. The alkene is 
(a) CH₃CH2CH = CH₂
(b) CH₃CH = CHCH₃
(c) (CH₃)₂C=CH₂
(d) CH₃CH= CH₂     
Answer: b

Question. Ammoniacal cuprous chloride will give red precipitate with which one of the following ? 
(a) CH₃ —C = C—CH₃
(b) CH₃ —CH = CH₂
(c) CH₃ —C=CH
(d) CH₃ —CH= CH—CH₃   
Answer: c

Question. LPG mainly contains 
(a) ethyne
(b) butane
(c) methane
(d) ethane     
Answer: b

Question. Petroleum is obtained from water gas, name of the reaction involved is 
(a) Fischer-Tropsch
(b) Bengoic
(c) Dow’s
(d) Kjeldahl’s     
Answer: a

Question. Which of the following is correct number of carbon atom present as the constituent of kerosene oil ?
(a) C₁₀—C₁₆
(b) C₄—C₆
(c) C₈—C1₆
(d) C₁₂—C₁₈ 
Answer: a

Question. In the reactions,
     _{Lindlar catalyst/ H2                      Na/NH}         
B          ←                  RC = CR       →     A
                                                     H₂                                    
A and B are geometrical isomers. Then,
(a) A is cis and Bis trans
(b) A is trans and B is cis
(c) A and Bare cis
(d) A and B are transA     
Answer: b

 Question. HBr reacts with CH₂= CH—OCH₃ under anhydrous conditions at room temperature to give 
(a) CH₃CHO and CH₃Br
(b) BrCH₂CHO and CH₃OH
(c) BrCH₂ — CH₂ — OCH₃
(d) H₃C — CHBr— OCH₃     
Answer: d 

Question. What are X and Y respectively in the following reaction?
Z-product ←^Y 2-butyne →^X E- product
(a) Na/NH₃ (liq.) and Pd/BaSO₄ + H₂
(b) Ni/140°C and Pd/BaSO₄ + H₂
(c) Ni/140°C and Na/NH3(liq.)
(d) Pd/BaSO₄ + H₂ and Na/NH₃(liq.) 
Answer: a   

Question. The dihalogen derivative X of a hydrocarbon with three carbon atoms reacts with alcoholic KOH and produces another hydrocarbon which forms a red precipitate with ammoniacal Cu₂Cl₂ . X gives an aldehyde on reaction with aqueous KOH. The compound Xis 
(a) 1, 3-dichloropropane
(b) 1, 2-dichloropropane
(c) 2, 2-dichloropropane
(d) 1, 1-dichloropropane
(e) 1, 3-dichloropropene 
Answer: a

Question. The treatment of CH₃MgX with CH₃C=C- H produces 
(a) CH₃ -CH= CH2
(b) CH₃C = C—CH₃
                H   H
                l    l
(c) CH₃ —C= C—CH₃
(d) CH₄       
Answer: d

Question. Identify Bin the following reaction,
CH₂=CH₂ + HCl →^Anhy.AICl3 A + 2[H] →^Zn-Cu B + HCI
                                                                      ^C₂H₅OH 
(a) CH₄
(b) C₂H₆
(c) C₂H₅CI
(d) C₂H₅OH 
Answer: b 

Question. Which one of the following has the minimum boiling point? 
(a) n-butane
(b) 1-butyne
(c) I-butene
(d) Iso-butene
Answer: d

Question. In the following reaction,
RCH₂CH= CH₂ + ICI → A
Markownikoff’s product A is 
(a) RCH₂ CH—CH₂I
               l
              Cl 
(b) RCH₂ CH—CH2CI
              l
              I
(c) RCH₂—C=CH₂
                l
                I
(d) RCH=CH—CH₂I
Answer: a

Question. CH₃ CH₃ + HNO₃ →^{675 K} ?
(a) CH₃CH₂NO₂
(b) CH₃CH₂NO₂ + CH₃NO₂
(c) 2CH₃NO₂
(d) CH₂ = CH₂     
Answer: b