Name: __________________
Topic 18: Organic III
Homework booklet
Topic Pages Due in date
1 Structure of Benzene
2 Electrophilic Substitution
3 Nitrogen-Containing
Organic Compounds
4 Condensation Polymers
and Amino Acids
5 Synthesis I
6 Synthesis II
, Homework 1 – Structure of Benzene
Consolidation Complete the questions on current topic
Revision Answer the recap questions
Preparation Pre-read pages in the textbook
Complete the questions based on this
Reflection N/A
Extra
Consolidation
Q3.
Describe how the orbitals from carbon atoms interact to form the bonds in a benzene ring. You may
include a labelled diagram to support your answer.
(3)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
2
,Q6.
Benzene is sometimes represented as Structure X, shown below, called a Kekulé structure after the
chemist who suggested it.
(a) What structural feature of benzene shows that Structure X is not an accurate representation?
(1)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(b) The enthalpy changes for the formation of cyclohexane from cyclohexene and from the actual
structure of benzene are given below.
(i) Use the necessary data to estimate the enthalpy change for the theoretical conversion of Structure
X to cyclohexane.
(1)
(ii) On the enthalpy level diagram below, draw labelled horizontal lines to show the relative enthalpies
of the actual structure of benzene, Structure X and cyclohexane. Add an arrow to show the enthalpy
change from Structure X to benzene and calculate the value of this enthalpy change in kJ mol−1. Write
this value next to your arrow.
(2)
, Q10.
(a) Equations for the catalytic hydrogenation of cyclohexene and of benzene are shown below.
(i) What is the type of reaction in both of these hydrogenations?
(1)
.............................................................................................................................................
*(ii) The enthalpy of hydrogenation of benzene might be expected to be −360 kJ mol−1.
Explain why this is not the actual value.
(2)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(iii) Complete the following equation for the total hydrogenation of phenylethene.
Suggest a value for the enthalpy change of this reaction.
(3)
ΔH = ................................................. kJ mol−1
Topic 18: Organic III
Homework booklet
Topic Pages Due in date
1 Structure of Benzene
2 Electrophilic Substitution
3 Nitrogen-Containing
Organic Compounds
4 Condensation Polymers
and Amino Acids
5 Synthesis I
6 Synthesis II
, Homework 1 – Structure of Benzene
Consolidation Complete the questions on current topic
Revision Answer the recap questions
Preparation Pre-read pages in the textbook
Complete the questions based on this
Reflection N/A
Extra
Consolidation
Q3.
Describe how the orbitals from carbon atoms interact to form the bonds in a benzene ring. You may
include a labelled diagram to support your answer.
(3)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
2
,Q6.
Benzene is sometimes represented as Structure X, shown below, called a Kekulé structure after the
chemist who suggested it.
(a) What structural feature of benzene shows that Structure X is not an accurate representation?
(1)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(b) The enthalpy changes for the formation of cyclohexane from cyclohexene and from the actual
structure of benzene are given below.
(i) Use the necessary data to estimate the enthalpy change for the theoretical conversion of Structure
X to cyclohexane.
(1)
(ii) On the enthalpy level diagram below, draw labelled horizontal lines to show the relative enthalpies
of the actual structure of benzene, Structure X and cyclohexane. Add an arrow to show the enthalpy
change from Structure X to benzene and calculate the value of this enthalpy change in kJ mol−1. Write
this value next to your arrow.
(2)
, Q10.
(a) Equations for the catalytic hydrogenation of cyclohexene and of benzene are shown below.
(i) What is the type of reaction in both of these hydrogenations?
(1)
.............................................................................................................................................
*(ii) The enthalpy of hydrogenation of benzene might be expected to be −360 kJ mol−1.
Explain why this is not the actual value.
(2)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(iii) Complete the following equation for the total hydrogenation of phenylethene.
Suggest a value for the enthalpy change of this reaction.
(3)
ΔH = ................................................. kJ mol−1
