1.0 Organic: Aromatic Chemistry

Question 1

Naming benzene molecules.
-Amine -alkene -alcohols -acid

Answer 1

Phenylamine
Phenylethene
Phenol
Benzoic acid

Question 2

What type of reaction benzene goes through?

Answer 2

Electrophilic substitution

Question 3

Benzene bonding.(3)

Answer 3

1)each C has 3 covalent bonds
2)spare e- in p orbital overlap above and below
3)delocalisation of e- in pi cloud

Question 4

Benzene shape(3)

Answer 4

1)planar
2)hexagon 120• bond angle
3) C—C bond equal in lenght

Question 5

Benzene stability.(3)

Answer 5

1)cyclohexatriene expect ^H = -360 kJ mol-1
2) benzene is H is less exothermic by 150
3)benzene is more stable due to delocalisation of e- in p orbital

Question 6

Benzene ring.(2)

Answer 6

1)area of high electron density
2)react with electrophiles

Question 7

1.Electrophilic substitution/ Nitration
-reagents -conditions -products

Answer 7

1.conc H2SO4 and conc HNO3
2.acid catalyst
3.nitrobenzene

Question 8

Write an equation to show how the electrophile is generated .(2)

Answer 8

H2SO4 + HNO3&raquo_space; +NO2 + HSO4- + H20

Question 9

Write an equation to show how the catalyst is regenerated.(2)

Answer 9

HSO4- + H+&raquo_space; H2SO4

Question 10

Outline mechanism.(5)

Answer 10

1.arrow from benzene ring to +NO2
2. Half ring POSITIVE forms
3. Arrow from H to POSITIVE half ring
4. attached to NO2

Question 11

Overall equation for nitration.

Answer 11

Benzene + HNO3 > nitrobenzene + h20

Question 12

2. Electrophilic substitution/ Acylation
   Reagents conditions products

Answer 12

1.(CH3)COCl / ethanoyl
2. Catalyst AlCl3
3. Phenylethanone / benzeneketone

Question 13

2.1 - State the reactive intermediate /electrophile

Answer 13

-CH+CO

Question 14

2.2 write an equation to show how the catalyst is regenerated.(2)

Answer 14

AlCl4- + H+&raquo_space; AlCl3

Question 15

2.4 overall equation of acylation

Answer 15

Benzene + acyl chloride&raquo_space; phenylethanone + HCl