Recommended prior knowledge
Learners should understand what is meant by a homologous series and a functional group, they should be able to use terms such as electrophile, nucleophile, addition and substitution to describe organic reaction mechanisms. Learners should know and be able to apply the organic chem istry studied in Unit 4 of this Scheme of work. They should understand addition polymerisation.
Context
This unit extends the learners’ knowledge of organic chemistry to include more functional groups including arenes. It brings together much of the knowledge that learners have gained about the reactions of functional groups to be able to s ynthesise organic molecules. In addition this unit extends the study of polymerisation to include condensation polymerisation.
Outline
Learners will study the reactions of aromatic compounds including benzene and phenol and the characteristic reactions of carb oxylic acids, acyl chlorides, and organic nitrogen compounds. They will learn how to explain the relative acidity and basicity of certain compounds. Learners w ill study condensation polymerisation and how to use knowledge of monomers to deduce the repeat unit of a polymer. They will apply knowledge about optical isomerism to the synthesis of molecules designed for a specific purpose. They will also bring their knowledge from different units into one place in order to solve more complex organic synthesis problems.
This unit is broken down into the following areas:
Hydrocarbons 2
Phenol
Carboxylic acids, acid chlorides, and nitrogen compounds
Polymerisation and synthesis Teaching time
It is recommended that this whole unit should take approximately 18% of the course.
Unit 9.1: Hydrocarbons 2
Learning objectives Suggested teaching activities Learning resources
14.1.a (A Level compounds only) interpret and use the general,
You revisit 14.1.a (AS), and include the A Level compounds in bold.
Learners in pairs make a variety of molecular models, with some
Online
www.chemguide.co.uk
structural, displayed and skeletal formulae of the following classes of compound:
(i) alkanes, alkenes and arenes (ii) halogenoalkanes and
halogenoarenes
(iii) alcohols (including primary, secondary and tertiary) and phenols
(iv) aldehydes and ketones (v) carboxylic acids, esters and
acyl chlorides
(vi) amines (primary only), nitriles, amides and amino acids (Candidates will be expected to recognise the shape of the benzene ring when it is present in organic compounds. Knowledge of benzene or its compounds is not required for AS Level.)
Key concept Atoms and forces
from each of the classes listed in this LO.
Learners use these to practise drawing the general, structural, displayed and skeletal formulae for each molecule. (P) (Basic)
Provide worksheets for practising examples of drawing different types of formulae. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Past paper
Paper 13, Nov 2013, Q20
15.4.a
describe the chemistry of arenes as exemplified by the following reactions of benzene and methylbenzene:
(i) substitution reactions with chlorine and with bromine (ii) nitration
(iii) Friedel-Crafts alkylation and acylation
You revisit LO 14.3 regarding the shape of organic compounds including benzene
You introduce arenes including:
o behaviour
o bonding and the delocalisation of electrons around the ring.
o models showing the shape and bonding. (W) (Basic)
Learners’ practical e.g. Hill Practical 27.
Learners make a mind map or table of these reactions of benzene and methylbenzene.
Learners summarise:
Textbooks Hill Practical 27 Online
www.chemguide.co.uk
http://www.rsc.org/learn- chemistry/resource/res00000286/organic-molecules-day
Past Paper
(iv) complete oxidation of the side-chain to give a benzoic acid
(v) hydrogenation of the benzene ring to form a cyclohexane ring Key concepts Atoms and forces,
Patterns in chemical behaviour and reactions,
Chemical bonds
o reactions, conditions, type of reaction, and equation
o compare the same reaction for benzene with that for methylbenzene. (G) (Basic) (Challenging)
Provide worksheets for practising examples of reactions of benzene and methylbenzene. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Paper 42, June 2013, Q3 (a)
15.4.b
(i) describe the mechanism of electrophilic substitution in arenes, as exemplified by the formation of nitrobenzene and bromobenzene (ii) suggest the mechanism of
other electrophilic
substitution reactions, given data
(iii) describe the effect of the delocalisation of electrons in arenes in such reactions Key concepts
Atoms and forces,
Patterns in chemical behaviour and reactions,
Chemical bonds
Learners talk in pairs to define free radical, electrophile, nucleophile, addition, substitution.
Give learners choices: (P) (Basic)
o produce a poster to explain electrophilic substitution. Visual
o script and record an interview with the benzene ring and the attacking species. Auditory
o produce a physical representation using molecular models and modelling clay (e.g. Plasticine or Blu-tack) to represent the delocalised electrons and the electron pairs. Kinaesthetic
Learners deliver presentations. V and K learners must explain their presentations. (W) (Basic)
Peer-marking of presentations using mark scheme prepared by you.
(P) (F) (Basic) (Challenging)
Provide worksheets for practising examples of electrophilic substitution mechanism. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Past Paper
Paper 42, June 2013, Q3 (b)
15.4.c Learners sketch the electron density cloud for benzene and
interpret the difference in reactivity between benzene and chlorobenzene
Key concepts Atoms and forces,
Patterns in chemical behaviour and reactions,
Chemical bonds
chlorobenzene. (W) (Basic)
Learners talk in pairs to produce ideas to present to the group:
o what effect will the chlorine atom have on the electron density in the ring?
o what effect will this have on the reactivity of the ring towards electrophiles? (P) (Basic)
Learners present ideas to the group, you guide them to reach correct conclusion. (G) (Basic)
Learners’ written piece (to use this lesson plus research)
‘Comparing the reactivity of benzene and chlorobenzene with electrophiles’. (I) (H) (Basic)
15.4.d
predict whether halogenation will occur in the side-chain or in the aromatic ring in arenes
depending on reaction conditions
Key concept
Patterns in chemical behaviour and reactions
You teach the conditions under which halogenation occurs in:
o the ring
o the side chain. (W) (Basic)
Provide worksheets for practising examples. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
15.4.e
apply knowledge relating to position of substitution in the electrophilic substitution of arenes (see the syllabusData BookletTable 9)
Key concept
Patterns in chemical behaviour and reactions
You teach how substituents on the ring affect subsequent substitutions, see syllabus page 90. (W) (Basic)
Provide worksheets for practising examples. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
14.1.c
understand and use systematic nomenclature of simple aromatic molecules with one benzene ring and one or more simple
substituents, for example 3-nitrobenzoic acid, 2,4,6-tribromophenol
You explain the naming convention. (W) (Basic)
Provide worksheets for practising examples. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Unit 9.2: Phenol
Learning objectives Suggested teaching activities Learning resources
17.2.a
recall the chemistry of phenol, as exemplified by the following reactions:
(i) with bases (ii) with sodium
(iii) with diazonium salts (see also Section 20.1)
(iv) nitration of, and bromination of, the aromatic ring
Key concepts
Experiments and evidence, Patterns in chemical behaviour and reactions
Learners investigate practically e.g. Hill Practical 31 or Lainchbury Experiment 8.2.
Learners create a mind map or table of these reactions.
Provide worksheets for practising examples. Compare, contrast and explain the reactions of phenol with those of benzene and
methylbenzene, especially:
o the nitration and
o bromination substitution reactions. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Textbooks Hill Practical 31
Lainchbury Experiment 8.2 Online
http://www.rsc.org/learn- chemistry/resource/res00000547/the-chemical-properties-of-hydroxybenzene
Past Paper
Paper 43, Nov 2013, Q5 (a)(i)
17.2.b
describe and explain the relative acidities of water, phenol and ethanol
Key concept
Experiments and evidence
You revisit calculating [H+] from pH and pH from [H+]. (W) (Basic)
Learners write equilibrium expressions for the dissociation of water, phenol, and ethanol. (P) (Basic)
Learners’ practical testing water and solutions of phenol, and ethanol with universal indicator. (P) (Basic)
You compare acidity of water and ethanol using sodium metal. (G) (Basic)
Learners talk in pairs:
o what is the order of acidity?
o what is the reason for it? (P) (Basic)
Learners describe evidence and explain reasons for homework. (I) (H) (Basic)
Unit 9.3: Carboxylic acids 2, acid chlorides, and nitrogen compounds
Learning objectives Suggested teaching activities Learning resources
19.1.b (iv) only
describe the reactions of carboxylic acids in the formation of:
(i) salts, by the use of reactive metals, alkalis or carbonates (ii) alkyl esters
(iii) alcohols, by use of LiAl H4
(iv) acyl chlorides
You revisit 19.1.b, introducing (iv) which may not have been covered as part of the AS course. (W) (Basic)
Online
www.chemguide.co.uk www.s-cool.co.uk
19.1.c You introduce the reactions in which methanoic acid and Online
recognise that some carboxylic acids can be further oxidised:
(i) the oxidation of methanoic acid, HCO2H, with Fehling’s and Tollens’ reagents (ii) the oxidation of ethanedioic
acid, HO2CCO2H, with warm acidified manganate(VII) Key concept
Patterns in chemical behaviour and reactions
ethanedioic acid can be oxidised. (W) (Basic)
Learners’ practical titrating ethanedioic acid against acidified MnO4-. (G) (Basic)
Provide worksheets for practising examples and equations for reactions of carboxylic acids to include oxidation of methanoic acid and ethanedioic acid. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
http://www.chemguide.co.uk/organicprops/carbo nyls/oxidation.html
19.1.d
explain the relative acidities of carboxylic acids, phenols and alcohols
Key concept
Patterns in chemical behaviour and reactions
Learners research into relative acidity of carboxylic acids, phenols, and alcohols. To include:
o examples of reactions with equations
o pK a values
o explanation. (I) (H) (Basic)
Learners deliver presentations. (W) (Basic)
Peer-marking of presentations using mark scheme prepared by you.
(P) (F) (Basic) (Challenging) 19.1.e
use the concept of
electronegativity to explain the acidities of chlorine-substituted ethanoic acids
Key concepts Chemical bonds, Energy changes
You can include this piece of research and presentation alongside 19.1.d.
Learners research into relative acidity of ethanoic acid and chlorine-substituted ethanoic acids. To include:
o pK a values
o explanation involving electronegativity. (I) (H) (Basic)
Learners deliver presentations. (W) (Basic)
Peer-marking of presentations using mark scheme prepared by you.
(P) (F) (Basic) (Challenging) 19.2.a
describe the hydrolysis of acyl
You demonstrate this practically, e.g. Lainchbury Experiment 10.2.
(W) (Basic)
Textbooks
Lainchbury Experiment 10.2
chlorides Key concept
Experiments and evidence
Learners write up practical with observations and equations. (I) (H) (Basic)
19.2.b
describe the reactions of acyl chlorides with alcohols, phenols, ammonia and primary amines Key concepts
Experiments and evidence, Patterns in chemical behaviour and reactions
You demonstrate these reactions practically. (W) (Basic)
Learners write up practical with observations and equations. (I) (H) (Basic)
Learners’ paired work, each learner describes a reaction of a named acid chloride, their partner has to write the observations and equation. Learners then change roles until at least two of each reaction in 19.2 a and b have been covered. (P) (F) (Basic) (Challenging)
Textbooks
Lainchbury Experiment 10.2
17.1.a (vii) only
recall the chemistry of alcohols, exemplified by ethanol, in the following reactions:
(i) combustion (ii) substitution to give
halogenoalkanes (iii) reaction with sodium (iv) oxidation to carbonyl
compounds and carboxylic acids
(v) dehydration to alkenes (vi) formation of esters by
esterification with carboxylic acids
(vii) formation of esters by acylation with acyl chlorides using ethyl ethanoate and phenyl benzoate as
Learners extend paired work from previous lesson to include reaction of acid chlorides to form ethyl ethanoate and phenyl benzoate. (P) (F) (Basic) (Challenging)
Online
http://www.chemguide.co.uk/organicprops/acylc hlorides/oxygen.html
examples Key concept
Patterns in chemical behaviour and reactions
19.2.c
explain the relative ease of hydrolysis of acyl chlorides, alkyl chlorides and aryl chlorides including the condensation (additionelimination) mechanism for the hydrolysis of acyl
chlorides
You show the equations with conditions for the hydrolysis of ethanoyl chloride to form ethanoic acid and for chloroethane to form ethanol. (W) (Basic)
Learners brainstorm reasons why acid chlorides are easier to hydrolyse than halogenoalkanes, which are easier to hydrolyse than aryl chlorides (e.g. chlorobenzene). (P) (Basic)
Learners discuss their ideas and rank them from the most to the least likely / possible. (W) (Basic)
You bring this together and also teach the addition / elimination mechanism. (G) (Basic)
Provide worksheets for practising examples of hydrolysis reactions and explaining relative ease of hydrolysis. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic) 20.1.a
describe the formation of alkyl amines such as ethylamine (by the reaction of ammonia with halogenoalkanes; the reduction of amides with LiAl H4; the reduction of nitriles with LiAl H4 or H2 /Ni)
and of phenylamine (by the reduction of nitrobenzene with tin/ concentrated HCl )
Learners research the methods of forming amines. To include:
o preparation of ethylamine and phenylamine equations
o conditions
o video clips if possible
Learners deliver presentations. (W) (Basic)
Peer-marking of presentations using mark scheme prepared by you.
(P) (F) (Basic) (Challenging)
Practical Booklet 11 Online
http://www.youtube.com/watch?v=oRn7kTiqfaA
20.1.b
describe and explain the basicity of amines
Key concept
Patterns in chemical behaviour and reactions
Give learners choices: (P) (Basic)
o produce a poster to explain why amines are basic. Visual
o script and record an interview with an amine and a hydrogen ion.
Auditory
o produce a physical representation using molecular models and blu-tack for lone pairs. Kinaesthetic
Learners deliver presentations; visual and kinaesthetic learners will need to explain their presentations. (W) (Basic)
Peer-marking of presentations using mark scheme prepared by you.
(P) (F) (Basic) (Challenging)
Practical Booklet 11
20.1.c
explain the relative basicities of ammonia, ethylamine and phenylamine in terms of their structures
Key concepts Atoms and forces,
Patterns in chemical behaviour and reactions,
Chemical bonds
Learners brainstorm what factors will affect basicity. (P) (Basic)
Brainstormed ideas brought together. (W) (Basic)
You lead discussion to a correct conclusion. (W) (Basic)
Provide worksheets for practising examples. To include:
o formation of amines
o reason for basicity of amines
o relative basicity of amines. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Practical Booklet 11 Past Paper
Paper 41, June 2013, Q4 (c)
20.1.d
describe the reaction of phenylamine with:
(i) aqueous bromine (ii) nitrous acid to give the
diazonium salt and phenol Key concept
Experiments and evidence
Learners investigate practically e.g. Hill Practical 34 or Lainchbury Experiment 8.3. (G) (Basic)
Learners write up practicals. (I) (H) (Basic)
Practical Booklet 11 Textbooks
Hill Practical 34
Lainchbury Experiment 8.3 Past Paper
Paper 42, June 2013, Q3 (d)
20.1.e Learners investigate practically. (G) (Basic) Practical Booklet 11
describe the coupling of benzenediazonium chloride and phenol and the use of similar reactions in the formation of dyestuff
Key concept
Experiments and evidence
Learners write up practical, including:
o the conditions with reasons
o observations
o equations
o the use of the product as a dye. (I) (H) (Basic)
Provide worksheets for practising examples of reactions of phenylamine. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Online
http://www.rsc.org/learn- chemistry/resource/res00000559/the-microscale-synthesis-of-azo-dyes www.chemguide.co.uk
20.2.a
describe the formation of amides from the reaction between NH3or RNH2and R’COCl
You teach this as a whole group activity. (W) (Basic) Past Paper
Paper 41, Nov 2013, Q5 (e)
20.2.b
recognise that amides are neutral
Key concept Atoms and forces,
Patterns in chemical behaviour and reactions
You show various amides in solution in test tubes and add indicator to them.
You explain why the structure does not accept a proton easily on the NH2 group (and so is not basic) and why it does not release a proton easily (and so is not acidic). (W) (Basic)
20.2.c
(i) describe amide hydrolysis on treatment with aqueous alkali or acid
(ii) describe the reduction of amides with LiAl H4
Key concept
Patterns in chemical behaviour and reactions
Learners investigate practically, refluxing an amide with hydrochloric acid and/or sodium hydroxide solution (separately). (G) (Basic)
Learners research products of amide hydrolysis and the reduction of amides to nitriles. (P) (Basic)
Learners deliver presentations. (W) (Basic)
Peer-marking of presentations using mark scheme prepared by you.
(P) (F) (Basic) (Challenging)
Provide worksheets for practising questions on amides. (I) (H) (Basic)
Practical Booklet 10
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic) 20.3.a
describe the acid/base properties of amino acids and the formation of zwitterions
Key concepts Atoms and forces,
Chemical bonds
Learners make molecular models of various amino acids such as alanine, valine and glycine.
Learners discuss why amino acids can be both acids and bases. (G) (Basic)
Learners draw out the structures of amino acids in acidic and basic environments and at the isoelectric point (the zwitterion). (P) (Basic)
Past Paper
Paper 41, Nov 2013, Q6 (b)(ii) (d)
20.3.b
describe the formation of peptide bonds between amino acids to give di- and tri-peptides Key concept
Chemical bonds
You explain formation of peptide bonds. (W) (Basic)
Learners use models of amino acids made last lesson to model formation of di-peptides and tri-peptides. (P) (Basic)
Past Papers
Paper 41, Nov 2013, Q6 (a) Paper 43, Nov 2013, Q6 (e)
20.3.c
describe simply the process of electrophoresis and the effect of pH, using peptides and amino acids as examples
Key concept Atoms and forces
Learners create a simulation
o five pieces of paper, each one is an amino acid (one each of lysine, glutamic acid, glycine, leucine and phenylalanine)
o they are put in the middle of the table, one side is positive, the opposite side is negative, the pH is 7
o lysine goes to negative side, glutamic acid goes to positive side, others stay in the middle, you explain why.
o the pH now becomes 12. You discuss what happens with the learners, due to magnitude of charge and molecular mass.
Learners ‘run the simulation’.
o the pH now becomes 2. You discuss what happens with the learners, due to magnitude of charge and molecular mass.
Learners ‘run the simulation’.
Learners discuss what effects pH has on the movement of amino
Practical Booklet 12 Past Paper
Paper 41, Nov 2013, Q7 (a)(b)
acids in an electric field. (P) (Basic)
Provide worksheets for practising questions about amino acids. (I) (H) (Basic)
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Unit 9.4: Polymerisation and synthesis
Learning objectives Suggested teaching activities Learning resources
8.3.e
outline the different
characteristics and modes of action of homogeneous, heterogeneous and enzyme catalysts, including:
(i) the Haber process (ii) the catalytic removal of
oxides of nitrogen from the exhaust gases of car engines (see also LO 15.3.b(i))
(iii) the catalytic role of atmospheric oxides of nitrogen in the oxidation of atmospheric sulfur dioxide (see also LO 13.1.f) (iv) the catalytic role of Fe2+or
Fe3+in theI – /S2O82 –reaction (v) the catalytic role of enzymes
(including the explanation of specificity using a simple lock and key model but
You reintroduce all catalysts in their contexts from LO 7.1.g, 8.1.d, 15.3.b (i), and 13.1.f and use as examples of homogeneous and heterogeneous catalysts. (W) (Basic)
Learners given choice:
o produce a poster to explain enzyme action. Visual
o script and record a conversation between the enzyme and its substrate. Auditory
o make models of enzyme and substrate and show how the enzyme works. Kinaesthetic
Learners deliver presentations. Kinaesthetic and visual learners should introduce their presentations. (W) (Basic)
Peer-marking of presentations using mark scheme prepared by you.
(P) (F) (Basic) (Challenging)
Provide worksheets for practising recalling and describing these examples of catalysis.
Peer-marking of worksheets using mark scheme prepared by you.
(P) (F) (Basic)
Textbooks Hill Planning, S9
excluding inhibition) 23.1.a
state that most chiral drugs extracted from natural sources often contain only a single optical isomer
Key concept Atoms and forces
Learners research:
o the chirality in naturally occurring compounds (such as carbohydrates or L-amino acids)
o the extraction of drugs from natural sources.
o chirality in natural and artificial drugs. (P) (H) (Basic)
Learners deliver presentations. (W) (Basic)
23.1.b
state reasons why the synthetic preparation of drug molecules often requires the production of a single optical isomer, e.g.
better therapeutic activity, fewer side effects
Key concept Atoms and forces
Learners research:
o the idea of one optical isomer being a better form of a drug than another.
o problems that have arisen due to chiral drugs. (P) (H) (Basic)
Learners deliver presentations. (W) (Basic)
12.4.a
describe the types of stereoisomerism shown by complexes, including those associated with bidentate ligands:
(i) trans isomerism, e.g. cis-and trans-platin Pt(NH3)2Cl 2
(ii) optical isomerism, e.g.
[Ni(NH2CH2CH2NH2)3]2+
Key concept
Learners make models of these complexes and then draw the structures in of the platins in 2-D and the optical isomers in 3-D. (P) (Basic)
Online
http://www.chemguide.co.uk/inorganic/complexi ons/shapes.html
Atoms and forces
12.4.b
describe the use of cisplatin as an anticancer drug and its action by binding to DNA in cancer cells, preventing cell division
Learners could research the action of cisplatin as a chemotherapy drug and present their findings in less than 250 words. (I) (Basic)
Learners could research the action of cisplatin as a chemotherapy drug and present their findings in less than 250 words. (I) (Basic)