Chemical Reactions of Alkanes and Alkenes

1. Structurecyclohexane cyclohexene

Or

CH2

CH2

CH2

CH2

CH2

CH2

C

C

C

C

C

C

H

H

H HH

H

H

HH H

H

H

Or

CH2

CH2

CH2

CH2

CH

CH

C

C

C

C

C

C

H

H HH

H

H

HH H

H

Table: 2-7

Cyclohexane Cyclohexene Polarity Non-polar Non-polar

Solubility Insoluble Insoluble H2SO4 None Cloudy

Br2 before Orange Orange Br2 after Orange Colourless KMnO4 Purple Purple KMnO4 Purple Brown

Question 1 - 51. Insoluble because they are non-polar.

Water is polar. Like-dissolves-like.

2. Alkanes: unreactive, Alkenes: most

3. A double bond has both

4. Weaker, projects outward

5. a) addition

b) it was the (acid) catalyst

c) accelerates a reaction without being used up

5 d) Cyclohexene + H2SO4 + H2O

cyclohexanole) Found in water because it has a polar

moiety (it is polar)

f) cyclohexanol (the product / the one to the right)

C

C

C

C

C

C

H

H H

H

H

H H

H

H

H

+C

C

C

C

C

C

H

H HH

HH H

H

H

H

OH

HOH2

catalyst

6 a-d: Cyclohexene + Br2

a) Orange

b) Addition

c)

C

C

C

C

C

C

H

H H

H

H

H H

H

H

H

+ Br BrC

C

C

C

C

C

H

H HH

HH H

H

H

H

Br

Br

d) Bromine was used up (disappeared)

7 : Cyclohexene + KMnO4

C

C

C

C

C

C

H

H H

H

H

H H

H

H

H

+C

C

C

C

C

C

H

H HH

HH H

H

H

H

OH

OHOH2

KMnO4

+ KOH + MnO2

C. Cyclohexene + Br

C

C

C

C

C

C

H

H H

H

H

H H

H

H

H

+ Br BrC

C

C

C

C

C

H

H HH

HH H

H

H

H

Br

Br

Isomers: cis-1,2-dibromocyclohexane

trans-1,2-dibromocyclohexane

E. Cyclohexene + KMnO4

Isomers: cis-1,2-cyclohexanediol

trans-1,2-cyclohexanediol

C

C

C

C

C

C

H

H H

H

H

H H

H

H

H

+C

C

C

C

C

C

H

H HH

HH H

H

H

H

OH

OHOH2

KMnO4

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