The document outlines revisions made to the chemistry syllabus between versions 9647 and 9729. Key changes include reorganizing topics into core ideas, making learning outcomes more explicit, and emphasizing fundamental concepts over specific examples. Specific topics like protein structure and Group 2/17 chemistry were moved or removed. Terminology, representations, and mechanisms are now clearly defined. Reaction conditions and complexation are discussed at a conceptual rather than numerical level.

1. Extension Topic
Extension Topic
Extension Topic
Extension Topic
Core Idea 3
(Transformation)
Core Idea 3
(Transformation)
Core Idea 3
(Transformation)
Core Idea 3
(Transformation)
Core Idea 2
(Structure & Properties)
Core Idea 2
(Structure & Properties)
Core Idea 2
(Structure & Properties)
Core Idea 2
(Structure & Properties)
Core Idea 1
(Matter)
Shapes of orbitals
§9647 To describe the shapes of s and p orbitals only
§9729
To describe the shapes of s and p orbitals
To describe the shapes of d orbitals
[knowledge of wave functions is not required]
No changes made
No changes made
To use the standard Gibbs free energy change of
reaction, ΔG, to predict the spontaneity of a reaction
§9647
Limitations of using ΔG are not explicitly
stated in Learning Outcomes
§9729
Learning outcomes explicitly state that
limitations of this use must be understood
§9647
This topic is subsumed under
the umbrella of Equilibria
Relationship between ΔG and the position of
equilibrium is not included
§9729 Standalone ‘Core Idea’
To show understanding that position of equilibrium is dependent on ΔG
[Quantitative treatment is not required]
Dalton’s Law
§9647 Not included
§9729
Dalton’s Law and its use in determining
the partial pressures of gases in a mixture
ALL chemical bonds (i.e. ionic,
covalent and metallic bonds)
are electrostatic in nature
§9647 Concept is implied
§9729 Concept is now emphasised
To reduce student misconceptions about
chemical bonding
To view classification of chemical bonds on
a continum rather than as discrete
descriptions
Bond polarities & polarity of molecules
§9647
Relationships between bond polarities and electronegativites, bond
polarities and molecular polarity are not explicitly stated as Learning
Outcomes
§9729
Learning Outcomes pertaining to explanation and deduction of bond
polarity and molecular polarity using electronegativity concepts and
molecular shapes are explicitly stated
§9647 Subsumed under topic of (Ionic) Equilibria Only Brønsted-Lowry theory is included
§9729 Standalone ‘Core Idea’
Includes Arrhenius, Brønsted-Lowry and Lewis acid-base theories
To show understanding of, and apply Lewis theory of acids and
bases to aqueous and non-aqueous systems (e.g. reaction
between BF3 and NH3)
Group names
§9647
Old IUPAC convention is used to label main groups -
Groups I, II, III, IV etc; transition elements are not labelled
§9729
New IUPAC convention is adopted -
Group III is now Group 13;
Group VII is now Group 17;
Group 0 is now Group 18 etc.
Variation with proton numbers
across Period 3 and down
Groups 2 and 17 of …
§9647
(i) atomic radius and ionic radius;
(ii) melting point;
(iii) electrical conductivity;
(iv) ionisation energy only
§9729
(i) atomic radius and ionic radius;
(ii) melting point;
(iii) electrical conductivity;
(iv) ionisation energy
(v) electronic configuration
(vi) electronegativity
Group 2 chemistry
§9647
Standalone topic classified under Inorganic Chemistry
To interpret and explain trend in thermal stability of NITRATES in
terms of charge density of the cation and polarisability of the large
anion
§9729
Subsumed under Core Idea of The Periodic Table
To interpret and explain trend in thermal stability of CARBONATES
in terms of charge density of the cation and polarisability of the
large anion
Group 17 chemistry
§9647
Standalone topic classified under Inorganic Chemistry
To describe and explain the reactions of halide ions with
(i) aqueous silver ions followed by aqueous ammonia;
(ii) concentrated sulfuric acid
Candidates are required to describe and analyse in terms of changes of oxidation
number the reaction of chlorine with cold, and with hot, aqueous sodium hydroxide
§9729
Subsumed under the Core Idea of The Periodic Table
Reactions between
(ii) halide ions and concentrated sulfuric acid
(iii) chlorine and aqueous sodium hydroxide
are no longer explicitly stated as Learning Outcomes
Reaction of halide ions with aqueous silver ions, followed by aqueous
ammonia, has been shifted to Solubility Equilibria, under the Extension
Topic (Chemistry of Aqueous Solutions)
Nitrogen Compounds
Basicity of amines§9729
To describe the reaction of amines in the formation of salts
Basicity of primary, secondary and tertiary amines in the GASEOUS
phase (interpret as LEWIS BASES)
Relative basicities of ammonia, ethylamine and phenylamine in aqueous medium
§9729
To describe the reduction to amines with lithium aluminium hydride
To explain why an amide is neutral in terms of delocalisation of the
lone pair of electrons on nitrogen
The term ‘condensation’ is formally used to name
the reactions of amines with acyl chlorides
Proteins
§9647
Includes structure of protein
(i) primary
(ii) secondary
(iii) tertiary
(iv) quaternary structures
Includes denaturation of proteins
§9729
Both the structure and denaturation of
proteins are removed
Only formation and hydrolysis of proteins remain
Carboxylic Acids & Derivatives§9729Reduction of carboxylic acids to primary alcohols, via reduction with
lithium aluminium hydride, using ethanol as an example
The term ‘condensation’ is formally used to name the reactions of acyl
chlorides with hydroxyl compounds and amines
Carbonyl Compounds§9729
Differences in reactivity between carbonyl compounds and alkenes
towards nucleophilic reagents, such as lithium aluminium hydride and
hydrogen cyanide
Halogen Derivatives§9729
More explicit articulation of what
teachers have been teaching all along
Examples
To describe and explain the nucleophilic substitution mechanisms in halogenoalkanes
(i) SN1, in terms of stability of the carbocation intermediates; racemisation
(ii) SN2, in terms of steric hindrance of the halogenoalkanes; inversion of configuration
(iii) The stereochemical outcome in nucleophilic substitution involving optically active substrates
To explain unreactivity of chlorobenzene compared to halogenoalkanes towards
nucleophilic substitution, in terms of delocalisation of the lone pair of electrons on
the halogen and steric hindrance
To suggest characteristic reactions to differentiate between
(i) different halogenoalkanes
(ii) halogenoalkanes and halogenoarenes, e.g. hydrolysis, followed by testing of the halide ions
Hydrocarbons
Electrophilic (aromatic)
substitution mechanism
§9647Mono-nitration of benzene
§9729
Mono-nitration of benzene is replaced by
mono-bromination of benzene
§9729
Greater clarity in the description and
differences in the chemistry of
alkanes, alkenes and arenes
Examples
To ‘explain’, rather than just ‘recognise’ the general
unreactivity of alkanes, including towards polar reagents
To explain general reactivity of alkenes towards
electrophilic reagents / electrophiles
Electrophilic addition of of water / steam, hydrogen halides
and halogens is differentiated from catalytic hydrogenation
or catalytic addition of hydrogen
Learning Outcomes explicitly requires candidates to explain the difference
between benzene and alkene reactivity
(i) towards electrophiles
(ii) preference of benzene to undergo substitution rather than addition reaction
Markovnikov’s Rule, as applied to
alkenes, is back in the syllabus
To apply the rule to the addition of hydrogen halides to unsymmetrical
alkenes, and explain the composition of products in terms of the
stability of carbocation intermediates
Friedel-Crafts alkylation of arenes with
halogenoalkanes is also back in the syllabus
To recognise that petroleum, a chemical feedstock, is a finite resource
and the importance of recycling
List of activating and deactivating groups is given in the Data Booklet
Isomerism
§9647Subsumed under topic of ‘Introductory Topics’
§9729
Standalone sub-topic under Extension Topic (Organic Chemistry)
Terminology that are no longer used
‘Structural isomerism’ is replaced by ‘constitutional isomerism’
‘Geometrical isomerism’ is replaced by ‘cis-trans isomerism’
‘Optical isomerism’ is replaced by ‘enantiomerism’
To help students understand that optical activity is a bulk property
rather than the property of individual molecules
Learning Outcomes explicitly states:
’to recognise that an optically active sample rotates
plane-polarised light and contains chiral molecules’
Introduction
Organic mechanisms§9729
Important aspects which teachers have been covering
on their own as part of mechanism drawing are now
formally incorporated
To interpret and use curly arrow notations to
represent movement of electrons in organic reaction
mechanisms
To recognise that mechanisms of polar reactions
involve flow of electrons from electron-rich to
electron-poor sites
Terminology for organic reactivities§9729
The following terms (which teachers have been using to explain relative reactivities
of molecules) are now formally incorporated into the new syllabus
(i) delocalisation;
(ii) electronic effect (electron-donating and electron-withdrawing effect);
(iii) steric effect (steric hindrance)
Terminology for organic reactions§9729
The following terms (which teachers have been using to describe organic reactions)
are now formally incorporated into the new syllabus
(ii) degree of substitution: primary, secondary, tertiary, quaternary;
(vi) Lewis acid (as electrophile), Lewis base (as nucleophile);
(vii) condensation
Representations of
organic molecules
§9647
Knowledge of stereochemical formula is merely
implied through the representation of optical isomers
§9729
The interpretation of the following representations is explicitly stated in
Learning Outcomes
(i) Empirical formula;
(ii) Molecular formula;
(iii) Structural formula;
(iv) Full structural or displayed formula;
(v) Skeletal formula;
(vi) Stereochemical formula
Practical conditions for
organic reactions
§9647
Syllabus does not explicitly state that candidates need not memorise
specific temperature and pressure values
§9729
Syllabus explicitly states that candidates need only know the essential
practical conditions, e.g. reflux, high temperature and pressure;
detailed conditions involving specific temperature and pressure values
are no longer required
Splitting of d orbitals
§9647
Not required to relate the shape and orientation of d orbitals to
the splitting of degenerate d orbitals
§9729
To describe, using the shape and orientation of d orbitals, the splitting of
degenerate d orbitals into two energy levels in octahedral complexes
Complexation reactions
§9647
Definitions for ligand and complex are not explicitly stated
To explain the reactions of transition elements with ligands to form
complexes,including the complexes of copper(ΙΙ) ions with water and ammonia
Complexes listed in the Qualitative Analysis Notes are not listed as Learning Outcomes
[Candidates tend to forget that these are also part of the syllabus too, since they only
use the Qualitative Analysis Notes during their practical assessment]
§9729
Learning Outcomes clearly list which complexes
candidates are required to study in greater detail
Define the terms ‘ligand’ and ‘complex’, as exemplified by
(i) the complexes of copper(II) ions with water, ammonia and chloride ions as ligands;
(ii) the transition metal complexes found in the Qualitative Analysis Notes
Contrast qualitatively a list of atomic and/or
physical properties of transition elements with
those of calcium as a typical s block element
§9647
(i) the melting point;
(ii) density;
(iii) atomic radius;
(iv) ionic radius;
(v) first ionisation energy;
(vi) conductivity
§9729
(i) the melting point;
(ii) density only
§9647The relationship ΔG = –nFE to electrochemical cells is not included
§9729
To state and apply the relationship ΔG = –nFE to electrochemical
cells, including the calculation of E for combined half reactions
§9647
The topics
- Acid-base Eqilibria
- Solubility Equilibria
are subsumed under the umbrella of Equilibria
§9729
The topics
- Acid-base Eqilibria
- Solubility Equilibria
are now subsumed under the Extension
Topic (Chemistry of Aqueous Solutions)
Reaction of halide ions with aqueous silver ions, followed by aqueous
ammoniam has been shifted to Solubility Equilibria (from Group VII
Chemistry in Syllabus 9647)