The most reactive hydrocarbon is : from Chemistry Hydrocarbons

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 Multiple Choice QuestionsMultiple Choice Questions

521.

Predict the product:


522.

The reduction of 4-octyne with H2 in the presence of Pd/CaSo4 quinoline gives:

  • trans-4-octene

  • cis-4-octene

  • a mixture of cis and trans-4-octene

  • a completely reduced product C8H18


523.

Addition of which of the following reagents to alkene is stereospecific:

I.Br2          II. KMnO4

III. BH3 THF/H2O2.NaOH

Select the correct reagent:

  • Both I and II

  • Both II and III

  • Both I and III

  • I, II and III


524.

Butyne-1 and butyne-2 can be distinguished by

  • H2SO4

  • AgNO3 + NH4OH

  • K2Cr2O7

  • NH4OH


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525.

An unknown silver salt of monoacidic alkyne contains 67.08% silver. The structure of the alkyne is:

  • CH3-CCH

  • CH3-CCH-CH3

  • CH3-CH2-CCH

  • CHCH


526.

What is obtained, when potassium succinate soluton is electrolysed ?

  • Ethane

  • Ethene

  • Ethyne

  • All of these


527.

CH3COOH P/Br2 CH2BrCOOH

This reaction is called

  • Schotton-Bauman reaction

  • Finkelstin reaction

  • Hell-Volhard-'Zelinsky reaction

  • none of the above


528.

Arrange the following in the decreasing order of their melting points:
I. Heptane      II. Octane
III. Nonane     IV. Decane

  • IV > II > III > I

  • IV > III > I > II

  • I > II > IV > III

  • II > III > I > IV


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529.

The most reactive hydrocarbon is :

  • methane

  • ethane

  • ethylene

  • acetylene


C.

ethylene

In ethylene H2C = CH2, the C - C bond distance is 1.34 Å, therefore, the π electrons of the double bond are easily exposed to the reactant (electrophiles) which readily react. In acetylene molecule HC  CH, although there are two π bonds but these electrons are not exposed to the attacking reagents due to small bond distance of C C bond (1.20 Å). A catalyst mercuric ion is therefore needed in reactions with actylene.


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530.

Which of the following is not a cumulated diene?

  • Hexa - 2 , 3 - diene

  • Penta - 1 , 3 - diene

  • Hexa - 1 , 2 - diene

  • Penta - 2 , 3 - diene


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