Chemical Properties of Alkynes

IMPORTANT

Chemical Properties of Alkynes: Overview

This topic covers concepts, such as, Chemical Reactions of Alkynes, Acidic Character of Terminal Alkynes, Reaction of Alkyne Due to Acidic Hydrogen & Reaction of Alkyne with Tollen's Reagent etc.

Important Questions on Chemical Properties of Alkynes

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When propyne is treated with aqueous  H 2 S O 4 in presence of  HgS O 4, the major product is:

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The product(s) obtained via hydration (HgSO4+H2SO4) of 1-butyne would be:

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The number of possible structural and configurational isomers of a bromo compound, formed by the addition of 1 mole of HBr to 2-pentyne respectively, are –

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How many reagents from the list below give effervescence when reacted with 1-pentyne?

NaOH(I), CH3CH2ONa(II), CH3CH2MgBr(III), NaH(IV), NaNH2(V), NaVI, NaHCO3(VII), (CH3)2CH2NLi(VIII), CH3CH2LiIX, C6H5LiX

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The total number structural isomers of alkynes that on catalytic reduction gives 3-ethyl-4-methylheptane are:

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In the following reaction

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X and Y, respectively, are

MEDIUM
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Match the following? 

 Reaction   Nature of reaction 
aRBrNa  (i) Partial reduction 
 (b) RCOO-Na+NaOHCaO,Δ  (ii) Electrophilic addition 
 (c) R-CC-R'  H2 Lindlar's catalyst  (iii) Wurtz reaction 
 (d) H2C=CH2Br2/CCl4  (iv) Decarboxylation 
   (v) Decarboxylative dimerization 

 

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Polymerisation product of propyne is

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Thin films of polyacetylene can be used as

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What would be the expected product of the reaction of propyne with Br2/H2O if the mechanism of this reaction is analogous to that of propene?(Bromoacetone/Bromopropanol)

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The treatment of CH 3 MgX with  CH 3 C C - H produces

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Identify A and B in the given reaction

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Ozonolysis followed by hydrolysis of pent-2-yne will produce:

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A hydrocarbon X with molecular formula C4H6 decolorizes bromine water and forms a white  precipitate in ethanolic AgNO3 solution Treatment of X with HgCl2 in aqueous H2SO4 produces a compound, which gives a yellow precipitate when treated with I2 and NaOH. The structure of X is :

MEDIUM
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The following conversion can be carried out by
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An organic compound X with molecular formula C6H10, when treated with HBr,  forms a gem dibromide. The compound X upon warming with HgSO4 and dil. H2SO4,  produces a ketone, which gives a positive iodoform test. The compound X is

EASY
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An alkyne XC4H6 forms sodium alkynide and when reacted with two molecules of HBr, it gave Y. What are X and Y?

MEDIUM
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A and B are ?

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