Aromatic Chemistry

Question 1

Why is benzene more stable then cyclohexane.

Answer 1

Delocalised ring of electrons

Question 2

What mechanism is used and the conditions

Answer 2

Electropholic additoon
-conc HNO3 and H2SO4
HN03 + 2H2SO4 ->NO2* + 2HS04’ + H3O+

Question 3

Write the equation show formation of this acylium ion

Answer 3

RCOCl + AlCl3 —> RCO* + AlCl4~

Question 4

Explain bonding in benzene

Answer 4

-each c has 3 covalent bonds
-spare electrons overlap
-delocalisation

Question 5

Explain shape in benzene

Answer 5

-planar
-6 carbon ring
-c-c bonds equal in length

Question 6

Explain stability in benzene

Answer 6

-benzene lower in energy than cyclohexane
-hydrogenation is less exothermic

Question 7

Predict a value for the enthalpy of hydrogenation of cyclohexane-1-3-diene

Answer 7

-239

Question 8

Explain why amine u is a weaker base than amine w

Answer 8

-electron pair of n
-delocalised
-less available

Question 9

Name type of linkage which broken suggest a suitable reagent

Answer 9

-peptide
-naOh

Question 10

Identity reagents and conditions needed for acylation

Answer 10

-Reagant -CH3COCl
-conditions -AlCl3