Which is the most suitable reagent among the following to distinguish compound (III) from rest of the compounds?                                                                                                 

I. CH3-CC-CH3

II. CH3-CH2-CH2-CH3

III. CH3-CH2-CCH

IV. CH3-CH=CH2

(a) Br2/CCl4                     (b) Br2/CH3COOH

(c)Alk.KMnO4                   (d) Ammonical AgNO3

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

(d) It may be noted that only the terminal alkynes react with ammonical silver nitrate. Therefore, this reaction can be used to distinguish between 1-alkynes and others such as alkane, alkenes and non-terminal alkynes.

     CH3-CH2-CCH + 2[Ag(NH3)2]NO3 CH3CH2CCAg

                                                                         white ppt.

Difficulty Level:

  • 19%
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Which of the following reagents will be able to distinguish between 1-butyne and 2-butyne?       

(a) NaNH2            (b) HCl             (c) O2                 (d) Br2

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

(a) NaNH2 is used to distinguish between 1-butyne and 2-butyne.

    CH3CH2CCHNaNH2CH3CH2CCNa  + 1/2 H2

     CH3-CC-H NaNH2No reaction

Difficulty Level:

  • 64%
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A compound is treated with NaNH2 to give sodium salt. Identify the compound.                      

(a) C2H2                  (b) C6H6

(c) C2H6                   (d) C2H4

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

(a) Sodamide is strong base, attract the more acidic hydrogen and gives sodium salt

  H-CC-H + NaNH2 H-CC-Na+    +  1/2 H2

                                    Sodium ethynide

Difficulty Level:

  • 63%
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When chlorine is passed through propene at 400°C, which of the following is formed?            

(a) PVC                         (b) Allyl chloride  

(c) Nickel chloride          (d) 1,2-dichloro ethane

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

(b) When chlorine gas is reacted with propene at high temperature (400°C), then substitution takes place in place of addition reaction. Hence, allyl chloride is formed.

 CH3-CH=CH2 + Cl2 400°CC|H2-CH=CH2 + HCl          Cl                                   

Difficulty Level:

  • 26%
  • 48%
  • 5%
  • 22%

When acetylene is passed through dil.H2SO4 in presence of HgSO4, the compound formed is

(a) ether                           (b) ketone

(c) acetic acid                    (d) acetaldehyde

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

(d) Hydration of alkyne, 

CHCH + H2OHg2+/H+TautomerisationCH3-CHO

Difficulty Level:

  • 8%
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Benzene reacts with CH3Cl in the presence of anhy. AlCl3 to form

(a) toluene

(b) chlorobenzene

(c) benzylchloride

(d) xylene

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

(a)  + CH3Cl Anhy. AlCl3

This reaction is known as Friedel-Craft's alkylation of benzene.

Difficulty Level:

  • 87%
  • 8%
  • 5%
  • 2%

In the following reaction,

 

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

Difficulty Level:

  • 70%
  • 8%
  • 20%
  • 5%

2-bromopentane is heated with potassium ethoxide in ethanol. The major product obtained is 

(a) 2-ethoxypentane                    (b)pentene-1

(c) trans-pentene-2                     (d) cis -pentene-2

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

(c)

Difficulty Level:

  • 32%
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CH3-CC-HCH3MgBrCH4 + (A)(ii) H2O/H+(i) CO2(B); (B) will be

(1) H3C-CH2-CH2-COOH                                (2) CH3-CC-CH3

(3) H3C-CC-COOH                                      (4) H3C-CH=CH-COOH

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

(3)  CH3-CC-HCH3MgBr H3C-CC-Mg+Br  (ii) H2O/H+(i) CO2H3C-CC-COOH   

                                          (A)                                         (B)

Difficulty Level:

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The monochlorinated products (excluding stereo-isomers) obtained from the reaction is:

(1) 4            (2) 5              (3) 6            (4) 7

 

Concept Videos :-

#12 | Differentiation: Alkanes, Alkenes & Alkynes
#13 | Differentiation: Assignment on Alkane to Alkyne
#18 | Addition Reaction: 1
#19 | Addition Reaction: 2
#6 | Chemical Properties of Alkane
#9 | Chemical Properties of Alkene:I
#10 | Reaction of Alkene:I
#11 | Reaction of Alkene:II
#14 | Preparation of Alkyne
#15 | Reaction of Alkyne:I

Concept Questions :-

Alkanes, Alkenes and Alkynes - Chemical Properties

Every unique position with replaceable H will result in a monochlorinated product

(1,5) (2,4 and (6,8) are identical positions. Therefore, five monochlorinated products can be formed.

 

Difficulty Level:

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