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CHEMISTRY

Higher 2 (2017)(Syllabus 9729)

CONTENTS

Page

INTRODUCTION 2

AIMS 2

PRACTICES OF SCIENCE 2

CURRICULUM FRAMEWORK 4

ASSESSMENT OBJECTIVES 5

SCHEME OF ASSESSMENT 6

ADDITIONAL INFORMATION 7

CONTENT MAP 8

SUBJECT CONTENT 10

PRACTICAL ASSESSMENT 31

SUMMARY OF KEY QUANTITIES AND UNITS 34

MATHEMATICAL REQUIREMENTS 36

GLOSSARY OF TERMS 37

TEXTBOOKS 38

DATA BOOKLET 39

PERIODIC TABLE 58

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9729 H2 CHEMISTRY (2017)

INTRODUCTION

Candidates will be assumed to have knowledge and understanding of Chemistry at O Level, as a singlesubject or as part of a balanced science course.

This syllabus is designed to place less emphasis on factual material and greater emphasis on theunderstanding and application of scientific concepts and principles. This approach has been adopted inrecognition of the need for students to develop skills that will be of long term value in an increasinglytechnological world rather than focusing on large quantities of factual material which may have only shortterm relevance.

Experimental work is an important component and should underpin the teaching and learning of Chemistry.

AIMS

The aims of a course based on this syllabus should be to:

1. provide students with an experience that develops interest in Chemistry and builds the knowledge, skills

and attitudes necessary for further studies in related fields

2. enable students to become scientifically literate citizens who are well-prepared for the challenges of the21st century

3. develop in students the understanding, skills, ethics and attitudes relevant to the Practices of Science,including the following:

3.1 understanding the nature of scientific knowledge

3.2 demonstrating science inquiry skills

3.3 relating science and society

4. develop the way of thinking to explain phenomena, approach and solve problems in chemicalsystemswhich involves students in:

4.1 understanding the structure, properties and transformation of matter at the atomic/molecular leveland how they are related to each other

4.2 connecting between the submicroscopic, macroscopic and symbolic levels of representations inexplaining and making predictions about chemical systems, structures and properties.

PRACTICES OF SCIENCE

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The Practices of Sciencecomprise three components:

1. Understanding the Nature of Scientific Knowledge

1.1 Understand that science is an evidenced-based, model-building enterprise concerned with thenatural world

1.2 Understand that the use of both logic and creativity is required in the generation of scientificknowledge

1.3 Recognise that scientific knowledge is generated from consensus within the community ofscientists through a process of critical debate and peer review

1.4 Understand that scientific knowledge is reliable and durable, yet subject to revision in the light ofnew evidence

2. Demonstrating Science Inquiry Skills

2.1 Identify scientific problems, observe phenomena and pose scientific questions/hypotheses

2.2 Plan and conduct investigations by selecting the appropriate experimental procedures, apparatusand materials, with due regard for accuracy, precision and safety

2.3 Obtain, organise and represent data in an appropriate manner

2.4 Analyse and interpret data

2.5 Construct explanations based on evidence and justify these explanations through reasoning andlogical argument

2.6 Use appropriate models1to explain concepts, solve problems and make predictions

2.7 Make decisions based on evaluation of evidence, processes, claims and conclusions

2.8 Communicate scientific findings and information using appropriate language and terminology

3. Relating Science and Society

3.1 Recognise that the application of scientific knowledge to problem solving could be influenced byother considerations such as economic, social, environmental and ethical factors

3.2 Demonstrate an understanding of the benefits and risks associated with the application of scienceto society

3.3 Use scientific principles and reasoning to understand, analyse and evaluate real-world systems aswell as to generate solutions for problem solving

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CURRICULUM FRAMEWORK

The key features of the H2 Chemistry Curriculum comprise Core Ideasand Extension Topics, Practices of

Scienceand Learning Experiencesas illustrated in Fig. 1.

Fig. 1: H2 Chemistry Curriculum Framework

1. Core Ideas and Extension Topics

The topics in H2 Chemistry are organised as two levels underpinned by the Practices of Science:

(a) Core ideas: The three Core Ideasof Chemistry are Matter, Structure and Properties, andTransformation. The concepts in these Core Ideasare inter-related and form the basis for which furtherlearning and understanding of chemical phenomena and reactions is built upon.

(b) Extension topics: Concepts in the Core Ideasextend into the learning of different chemical systemssuch as chemistry of organic compounds and transition elements. As an example, an understanding of

concepts of Chemical Bonding and The Periodic Table is extended to the study of the chemistry oftransition metals where students learn to appreciate the similarities and differences when comparingwith main group metals.

2. Practices of Science

The Practices of Scienceare common to the natural sciences of physics, chemistry and biology. These

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ASSESSMENT OBJECTIVES

TheAssessment Objectiveslisted below reflect those parts of theAimsand Practices of Sciencethat will be

assessed.

A Knowledge with understanding

Candidates should be able to demonstrate knowledge and understanding in relation to:

1. scientific phenomena, facts, laws, definitions, concepts and theories

2. scientific vocabulary, terminology and conventions (including symbols, quantities and units)

3. scientific instruments and apparatus, including techniques of operation and aspects of safety

4. scientific quantities and their determination

5. scientific and technological applications with their social, economic and environmental implications.

The syllabus content defines the factual knowledge that candidates may be required to recall and explain.Questions testing these objectives will often begin with one of the following words: define,state,name,

describe, explain oroutline(see the Glossary of Terms).

B Handling, applying and evaluating information

Candidates should be able (in words or by using symbolic, graphical and numerical forms of presentation) to:

1. locate, select, organise and present information from a variety of sources

2. handle information, distinguishing the relevant from the extraneous

3. manipulate numerical and other data and translate information from one form to another

4. analyse and evaluate information so as to identify patterns, report trends and conclusions, and drawinferences

5. present reasoned explanations for phenomena, patterns and relationships

6. apply knowledge, including principles, to novel situations

7. bring together knowledge, principles, concepts and skills from different areas of chemistry, and applythem in a particular context

8. evaluate information and hypotheses

9. construct arguments to support hypotheses or to justify a course of action

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C Experimental skills and investigations

Candidates should be able to:

1. follow a detailed set or sequence of instructions and use techniques, apparatus and materials safelyand effectively

2. make, record and present observations and measurements with due regard for precision and accuracy

3. interpret and evaluate observations and experimental data

4. identify a problem, devise and plan investigations, select techniques, apparatus and materials

5. evaluate methods and techniques, and suggest possible improvements.

SCHEME OF ASSESSMENT

All candidates are required to enter for Papers 1, 2, 3 and 4.

Paper Type of Paper Duration Weighting (%) Marks

1 Multiple Choice 1 h 15 30

2 Structured Questions 2 h 30 75

3 Free Response Questions 2 h 35 80

4 Practical 2 h 30 min 20 55

Paper 1(1 h, 30 marks)

This paper consists of 30 compulsory multiple choice questions. Five to eight items will be of the multiplecompletion type.

All questions will include 4 options.

Paper 2

(2 h, 75 marks)

This paper consists of a variable number of structured questions including data-based questions. Allquestions are compulsory and answered on the question paper. The data-based question(s) constitute(s)2025 marks for this paper.

The data-based question(s) provide(s) good opportunity to test higher order thinking skills such as handling

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Paper 4(2 h 30 min, 55 marks)

This paper will assess appropriate aspects of objectives C1 to C5 in the following skill areas:

Planning (P) Manipulation, measurement and observation (MMO)

Presentation of data and observations (PDO)

Analysis, conclusions and evaluation (ACE)

The assessment of Planning (P) will have a weighting of 5%. The assessment of skill areas MMO, PDO andACE will have a weighting of 15%.

The scope of the practical paper is indicated in the Practical Assessmentsection. The assessment of PDO andACE may also include questions on data-analysis which do not require practical equipment and apparatus.

Candidates will notbe permitted to refer to books and laboratory notebooks during the assessment.

Weighting of Assessment Objectives

Assessment Objectives Weighting (%) Assessment Components

AKnowledge withunderstanding

32 Papers 1, 2, 3

BHandling, applyingand evaluatinginformation

48 Papers 1, 2, 3

C Experimental skillsand investigations

20 Paper 4

ADDITIONAL INFORMATION

Data Booklet

A Data Booklet is available for use in the theory papers. The booklet is reprinted at the end of this syllabusdocument. The Qualitative Analysis Notes in the Data Booklet will be made available for use in the practicalassessment.

Nomenclature

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8

CONTENT MAP

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Chemistry is about the study of matter, its interactions and transformations. At a macroscopic level, weobserve matter and its interactions everywhere in our daily life. The submicroscopic level looks at thestructure of matter that gives rise to these interactions. At O Level, students have been introduced to thefundamental idea that matter is made up of particles and the simple atomic model (electrons in discrete

shells around a positively charged nucleus). This allows students to apply the key ideas of conservation ofmatter and energy in the quantitative treatment of reactions such as stoichiometry and thermochemistry.

At A Level, an in-depth study of the electronic structure of atoms provides the basis for the study of chemicalbonding. The Valence Shell Electron Pair Repulsion (VSEPR) model is used to visualise the three-dimensional structure of molecules, which determines the type of interactions possible and also helps toexplain the physical and chemical properties. Knowledge of structure and bonding is also important to studyand predict trends in properties of matter and its reactions. Modern organic chemistry is based on theconcept that the four valence bonds of a carbon atom are oriented in a tetrahedral configuration, which led to

the development of the stereochemical concept. This has important applications, particularly in thepharmaceutical industry as many drugs are active only in one particular enantiomeric form.

Transformation of matter involves the study of the feasibility (thermodynamics and kinetics considerations)and extent of chemical reactions (concept of equilibrium). The chemical thermodynamics dimension builds

upon prior knowledge of thermochemistry, mainly enthalpy changes (H). Together with entropy changes

(S), a mathematical relationship is established which gives the true measure of the thermodynamics

feasibility of a reaction the Gibbs free energy (G). For aqueous redox reactions, the more convenientnotion of electrode potential (E) is used, and the resultant cell potential (Ecell) gives a measure of

thermodynamics feasibility instead. The chemical kinetics facet of a reaction can be understoodquantitatively by relating the rate of reaction to concentration of reactants. The qualitative aspect which dealswith the factors affecting rate of reactions will be covered based on the collision theory.

The concepts in chemical thermodynamics and kinetics will form the basis for the study of ChemicalEquilibrium. Theoretically all reactions are reversible, and the notion of dynamic equilibrium will beintroduced. The concept of equilibrium constant (K) is understood via the equilibrium expression, which givesa measure of the extent of a reversible reaction. Factors which determine the position of equilibrium will alsobe examined. Chemical equilibria in aqueous media involving acids and bases will be dealt with in greater

depth, in view of the relevance and prevalence of these concepts which cuts across chemical systems.

This curriculum framework provides students the opportunity to appreciate the connections between theconcepts in the Core Ideasof Matter, Structure and Properties, and Transformation, and to apply theseto the study of different chemical systems in the Extension Topics.

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SUBJECT CONTENT

CORE IDEA 1 MATTER

1. Atomic Structure

Content

The nucleus of the atom: neutrons and protons, isotopes, proton and nucleon numbers

Electrons: electronic energy levels, ionisation energies, atomic orbitals, extranuclear structure

Learning Outcomes


(a) identify and describe protons, neutrons and electrons in terms of their relative charges and relativemasses

(b) deduce the behaviour of beams of protons, neutrons and electrons in an electric field

(c) describe the distribution of mass and charges within an atom

(d) deduce the numbers of protons, neutrons and electrons present in both atoms and ions given protonand nucleon numbers (and charge)

(e) (i) describe the contribution of protons and neutrons to atomic nuclei in terms of proton number andnucleon number

(ii) distinguish between isotopes on the basis of different numbers of neutrons present

(f) describe the number and relative energies of the s, p and d orbitals for the principal quantum numbers1, 2 and 3 and also the 4s and 4p orbitals

(g) describe the shapes of s, p and d orbitals (see also Section 13)

[knowledge of wave functions is notrequired]

(h) state the electronic configuration of atoms and ions given the proton number (and charge)

(i) explain the factors influencing the ionisation energies of elements (see the Data Booklet) (see alsoSection 5)

(j) deduce the electronic configurations of elements from successive ionisation energy data

(k) interpret successive ionisation energy data of an element in terms of the position of that element withinth P i di T bl

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CORE IDEA 2 STRUCTURE AND PROPERTIES

2. Chemical Bonding

Content

Ionic bonding, metallic bonding, covalent bonding and co-ordinate (dative covalent) bonding

Shapes of simple molecules and bond angles

Bond polarities and polarity of molecules

Intermolecular forces, including hydrogen bonding

Bond energies and bond lengths Lattice structure of solids

Bonding and physical properties

Learning Outcomes


(a) show understanding that all chemical bonds are electrostatic in nature and describe:(i) ionic bond as the electrostatic attraction between oppositely charged ions

(ii) covalent bond as the electrostatic attraction between a shared pair of electrons and positivelycharged nuclei

(iii) metallic bond as the electrostatic attraction between a lattice of positive ions and delocalisedelectrons

(b) describe, including the use of dot-and-cross diagrams,

(i) ionic bonding as in sodium chloride and magnesium oxide

(ii) covalent bonding as in hydrogen; oxygen; nitrogen; chlorine; hydrogen chloride; carbon dioxide;methane; ethene

(iii) co-ordinate (dative covalent) bonding, as in formation of the ammonium ion and in the Al2Cl6molecule

(c) describe covalent bonding in terms of orbital overlap (limited to s and p orbitals only), giving and bonds (see also Section 11.1)

(d) explain the shapes of, and bond angles in, molecules such as BF3(trigonal planar); CO2(linear); CH4(tetrahedral); NH3(trigonal pyramidal); H2O (bent); SF6(octahedral) by using the Valence Shell ElectronPair Repulsion theory

(e) predict the shapes of, and bond angles in, molecules analogous to those specified in (d)

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(j) explain the terms bond energyand bond lengthfor covalent bonds

(k) compare the reactivities of covalent bonds in terms of bond energy, bond length and bond polarity

(l) describe, in simple terms, the lattice structure of a crystalline solid which is:

(i) ionic, as in sodium chloride and magnesium oxide

(ii) simple molecular, as in iodine

(iii) giant molecular, as in graphite and diamond

(iv) hydrogen-bonded, as in ice

(v) metallic, as in copper

[the concept of the unit cell is notrequired]

(m) describe, interpret and/or predict the effect of different types of structure and bonding on the physicalproperties of substances

(n) suggest the type of structure and bonding present in a substance from given information

3. The Gaseous State

Content

Ideal gas behaviour and deviations from it

pV = nRT and its use in determining a value for Mr

Daltons Law and its use in determining the partial pressures of gases in a mixture

Learning Outcomes


(a) state the basic assumptions of the kinetic theory as applied to an ideal gas

(b) explain qualitatively in terms of intermolecular forces and molecular size:

(i) the conditions necessary for a gas to approach ideal behaviour

(ii) the limitations of ideality at very high pressures and very low temperatures

(c) state and use the general gas equationpV = nRT in calculations, including the determination of Mr

(d) use Daltons Law to determine the partial pressures of gases in a mixture (see also Section 9)

4. Theories of Acids and Bases

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5. The Periodic Table

Content

Periodicity of atomic and physical properties of the elements: variation with proton number across thethird period (sodium to chlorine) and down the group (Group 2 and Group 17) of:

(i) electronic configuration

(ii) atomic radius and ionic radius

(iii) ionisation energy

(iv) electronegativity

(v) melting point

(vi) electrical conductivity

Periodicity of chemical properties of the elements in the third period:

(i) variation in oxidation number and bonding of the oxides (sodium to sulfur only) and of the chlorides(sodium to phosphorus only)

(ii) reactions of these oxides and chlorides with water

(iii) acid/base behaviour of these oxides and the corresponding hydroxides

Periodicity of chemical properties of the elements down the group (Group 2 and Group 17):

(i) as reducing agents (Group 2) and oxidising agents (Group 17)

(ii) thermal stability of Group 2 carbonates and Group 17 hydrides

Learning Outcomes

Trends and variations in atomic and physical propertiesFor elements in the third period (sodium to chlorine), and in Group 2 (magnesium to barium) and Group 17(chlorine to iodine) candidates should be able to:

(a) recognise variation in the electronic configurations across a Period and down a Group

(b) describe and explain qualitatively the trends and variations in atomic radius, ionic radius, first ionisationenergy and electronegativity:

(i) across a Period in terms of shielding and nuclear charge

(ii) down a Group in terms of increasing number of electronic shells and nuclear charge

(c) interpret the variation in melting point and in electrical conductivity across a Period in terms of structureand bonding in the elements (metallic, giant molecular, or simple molecular)

(d) describe and explain the trend in volatility of the Group 17 elements in terms of instantaneous dipole-induced dipole attraction

Trends and variations in chemical properties

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For elements in Group 2 (magnesium to barium) and Group 17 (chlorine to iodine) candidates should beable to:

(f) describe and deduce from Evalues the relative reactivity of elements of:

(i) Group 2 as reducing agents

(ii) Group 17 as oxidising agents

(g) describe and explain the trend in thermal stability of:

(i) Group 2 carbonates in terms of the charge density of the cation and the polarisability of the largeanion

(ii) Group 17 hydrides in terms of bond energies

In addition, candidates should be able to:

(h) predict the characteristic properties of an element in a given Group by using knowledge of chemicalperiodicity

(i) deduce the nature, possible position in the Periodic Table, and identity of unknown elements from giveninformation of physical and chemical properties

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CORE IDEA 3 TRANSFORMATION

6. The Mole Concept and Stoichiometry

Content

Relative masses of atoms and molecules

The mole, the Avogadro constant

The calculation of empirical and molecular formulae

Reacting masses and volumes (of solutions and gases)

Learning Outcomes

[the term relative formula mass or Mrwill be used for ionic compounds]


(a) define the terms relative atomic, isotopic, molecularand formulamass, based on the12

C scale

(b) define the term molein terms of the Avogadro constant

(c) calculate the relative atomic mass of an element given the relative abundances of its isotopes

(d) define the terms empiricaland molecular formula

(e) calculate empirical and molecular formulae using combustion data or composition by mass

(f) write and/or construct balanced equations

(g) perform calculations, including use of the mole concept, involving:(i) reacting masses (from formulae and equations)

(ii) volumes of gases (e.g. in the burning of hydrocarbons)

(iii) volumes and concentrations of solutions

[when performing calculations, candidates answers should reflect the number of significant figuresgiven or asked for in the question]

(h) deduce stoichiometric relationships from calculations such as those in (g)

7. Chemical Energetics: Thermochemistry and Thermodynamics (Gibbs Free Energy andEntropy)

Content

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Learning Outcomes


(a) explain that most chemical reactions are accompanied by energy changes, principally in the form ofheat usually associated with the breaking and forming of chemical bonds; the reaction can beexothermic (Hnegative) or endothermic (Hpositive)

(b) construct and interpret an energy profile diagram, in terms of the enthalpy change of the reaction and ofthe activation energy (see also Section 8)

(c) explain and use the terms:

(i) enthalpy change of reactionand standard conditions, with particular reference to: formation;

combustion; hydration; solution; neutralisation; atomisation

(ii) bond energy(Hpositive, i.e. bond breaking) (see also Section 2)

(iii) lattice energy(Hnegative, i.e. gaseous ions to solid lattice)

(d) calculate enthalpy changes from appropriate experimental results, including the use of the relationship:heat change = mcT

(e) explain, in qualitative terms, the effect of ionic charge and of ionic radius on the numerical magnitude of

a lattice energy

(f) apply Hess Law to construct simple energy cycles, e.g. Born-Haber cycle, and carry out calculationsinvolving such cycles and relevant energy terms (including ionisation energy and electron affinity), withparticular reference to:

(i) determining enthalpy changes that cannot be found by direct experiment, e.g. an enthalpy changeof formation from enthalpy changes of combustion

(ii) the formation of a simple ionic solid and of its aqueous solution

(iii) average bond energies

(g) explain and use the term entropy

(h) discuss the effects on the entropy of a chemical system by the following:

(i) change in temperature

(ii) change in phase

(iii) change in the number of particles (especially for gaseous systems)

(iv) mixing of particles

[quantitative treatment is notrequired]

(i) predict whether the entropy change for a given process or reaction is positive or negative

(j) state and use the equation involving standard Gibbs free energy change of reaction, G:


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8. Reaction Kinetics

Content

Simple rate equations; orders of reaction; rate constants

Concept of activation energy

Effect of concentration, temperature, and catalysts on reaction rate

Homogeneous and heterogeneous catalysis

Enzymes as biological catalysts

Learning Outcomes


(a) explain and use the terms: rate of reaction; rate equation; order of reaction; rate constant; half-life of areaction; rate-determining step; activation energy; catalysis

(b) construct and use rate equations of the form rate = k[A]m[B]

n(limited to simple cases of single-step

reactions and of multi-step processes with a rate-determining step, for which mand n are 0, 1 or 2),including:

(i) deducing the order of a reaction by the initial rates method

(ii) justifying, for zero- and first-order reactions, the order of reaction from concentration-time graphs

(iii) verifying that a suggested reaction mechanism is consistent with the observed kinetics

(iv) predicting the order that would result from a given reaction mechanism

(v) calculating an initial rate using concentration data

[integrated forms of rate equations are not required]

(c) (i) show understanding that the half-life of a first-order reaction is independent of concentration

(ii) use the half-life of a first-order reaction in calculations

(d) calculate a rate constant using the initial rates method

(e) devise a suitable experimental technique for studying the rate of a reaction, from given information

(f) explain qualitatively, in terms of frequency of collisions, the effect of concentration changes on the rateof a reaction

(g) show understanding, including reference to the Boltzmann distribution, of what is meant by the termactivation energy

(h) explain qualitatively, in terms both of the Boltzmann distribution and of collision frequency, the effect oftemperature change on a rate constant (and hence, on the rate) of a reaction


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(k) describe enzymes as biological catalysts which may have specific activity

(l) explain the relationship between substrate concentration and the rate of an enzyme-catalysed reactionin biochemical systems

9. Chemical Equilibria

Content

Chemical equilibria: reversible reactions; dynamic equilibrium

(i) factors affecting chemical equilibria

(ii) equilibrium constants(iii) the Haber process

Learning Outcomes


(a) explain, in terms of rates of the forward and reverse reactions, what is meant by a reversible reactionand dynamic equilibrium

(b) state Le Chateliers Principle and apply it to deduce qualitatively (from appropriate information) theeffects of changes in concentration, pressure or temperature, on a system at equilibrium

(c) deduce whether changes in concentration, pressure or temperature or the presence of a catalyst affectthe value of the equilibrium constant for a reaction

(d) deduce expressions for equilibrium constants in terms of concentrations, Kc, and partial pressures, Kp

[treatment of the relationship between Kpand Kcis notrequired]

(e) calculate the values of equilibrium constants in terms of concentrations or partial pressures fromappropriate data

(f) calculate the quantities present at equilibrium, given appropriate data (such calculations will not requirethe solving of quadratic equations)

(g) show understanding that the position of equilibrium is dependent on the standard Gibbs free energy

change of reaction, G

[Quantitative treatment is notrequired]

(h) describe and explain the conditions used in the Haber process, as an example of the importance of anunderstanding of chemical equilibrium in the chemical industry


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EXTENSION TOPICS

10. Chemistry of Aqueous Solutions

10.1 Acid-base Equilibria

This topic deals with acid-base equilibria in aqueous solution. Hence the Brnsted-Lowry definitions ofacid/base are primarily used in the understanding of pH of solutions. (See Section 4)

Content

Acid dissociation constants, Kaand the use of pKa

Base dissociation constants, Kband the use of pKb The ionic product of water, Kw

pH: choice of pH indicators

Buffer solutions

Learning Outcomes


(a) explain qualitatively the differences in behaviour between strong and weak acids and bases in terms ofthe extent of dissociation

(b) explain the terms pH; Ka;pKa; Kb; pKb; Kwand apply them in calculations, including the relationshipKw= KaKb

(c) calculate [H+(aq)] and pH values for strong acids, weak monobasic (monoprotic) acids, strong bases,

and weak monoacidic bases

[Calculations involving weak acids/bases will notrequire solving of quadratic equations]

(d) describe the changes in pH during acid-base titrations and explain these changes in terms of thestrengths of the acids and bases

(e) explain the choice of suitable indicators for acid-base titrations, given appropriate data

(f) (i) explain how buffer solutions control pH

(ii) describe and explain their uses, including the role of H2CO3/HCO3

in controlling pH in blood

(g) calculate the pH of buffer solutions, given appropriate data

10.2 Solubility Equilibria


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(c) discuss the effects on the solubility of ionic salts by the following:

(i) common ion effect

(ii) formation of complex ion, as exemplified by the reactions of halide ions with aqueous silver ions

followed by aqueous ammonia (see also Section 13)

11. Organic Chemistry

Preamble

Although there are features of organic chemistry topics that are distinctive, it is intended that appropriatecross-references with other sections/topics in the syllabus should be made.

In their study of organic chemistry, candidates may wish to group the organic reactions in terms of themechanisms in the syllabus where possible. Candidates may wish to compare and contrast the differentmechanisms.

When describing preparative reactions, candidates will be expected to quote the reagents, e.g. aqueousNaOH, the essential practical conditions, e.g. reflux, high temperature and pressure, and the identity of eachof the major products. Detailed conditions involving specific temperature and pressure values are notrequired.

Detailed knowledge of practical procedures is also notrequired; however, candidates may be expected tosuggest (from their knowledge of the reagents, essential conditions and products) what steps may beneeded to purify/extract a required product from the reaction mixture. In equations for organic redoxreactions, the symbols [O] and [H] are acceptable.

11.1 Introduction

Content

Empirical, molecular and structural formulae

Functional groups and the naming of organic compounds

Common terms for organic reactions and reactivities

Shapes of organic molecules; and bonds

Candidates are expected to be able to interpret and use the following types of representations in the

description of organic molecules. The examples given are for the compound (+)-lactic acid.

Empirical Formula: simplest ratio of the number of atoms of the elements present in one molecule, e.g.CH2O

Molecular Formula: actual number of atoms of the elements present in one molecule, e.g. C3H6O3


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Skeletal Formula: simplified representation of an organic formula derived from the structural formula byremoving hydrogen atoms (and their associated bonds) and carbon atoms from alkyl chains, leaving just thecarbon-carbon bonds in the carbon skeleton and the associated functional groups

Skeletal or partial skeletal representations may be used in question papers and are acceptable incandidates answers where they are unambiguous, e.g.

CO2HH3C

OH

O

OH

OH

O

OHH3C

OH

skeletal partial skeletal

The convention for representing the aromatic ring is preferred.

Stereochemical Formula: show spatial arrangement of bonds, atoms and groups in molecule in 3-D, e.g.

When drawing a pair of optical isomers, candidates should indicate the three-dimensional structuresaccording to the convention used in the example below.

Candidates are expected to be able to interpret and use the curly arrow notation to represent the movementof electrons in organic reaction mechanisms.

For movement of apairof electrons (full arrow):

For movement of a singleunpaired electron (half arrow) :


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( )

Learning Outcomes


(a) interpret, and use the nomenclature, general formulae and displayed formulae of the following classesof compound:

(i) hydrocarbons (alkanes, alkenes and arenes)

(ii) halogen derivatives (halogenoalkanes and halogenoarenes)

(iii) hydroxyl compounds (alcohols and phenols)

(iv) carbonyl compounds (aldehydes and ketones)

(v) carboxylic acids and derivatives (acyl chlorides and esters)

(vi) nitrogen compounds (amines, amides, amino acids and nitriles)

(b) interpret, and use the following terminology associated with organic reactions:

(i) functional group

(ii) degree of substitution: primary, secondary, tertiary, quaternary

(iii) homolytic and heterolytic fission

(iv) carbocation

(v) free radical, initiation, propagation, termination(vi) electrophile (Lewis acid), nucleophile (Lewis base)

(vii) addition, substitution, elimination, condensation, hydrolysis

(viii) oxidation and reduction

[in equations for organic redox reactions, the symbols [O] and [H] are acceptable]

(c) interpret, and use the following terminology associated with organic reactivities:

(i) delocalisation(ii) electronic effect (electron-donating and electron-withdrawing effect)

(iii) steric effect (steric hindrance)

(d) describe sp3hybridisation, as in ethane molecule, sp

2hybridisation, as in ethene and benzene

molecules, and sp hybridisation, as in ethyne molecule

(e) explain the shapes of, and bond angles in, the ethane, ethene, benzene, and ethyne molecules in

relation to and carbon-carbon bonds

(f) predict the shapes of, and bond angles in, molecules analogous to those specified in (e)

(g) apply (b) and (c) to the understanding of mechanisms in terms of organic structure and bonding

(h) recognise that the mechanisms of polar reactions involve the flow of electrons from electron-rich to


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11.2 Isomerism

Content

Isomerism: constitutional (structural); cis-trans; enantiomerism

Learning Outcomes


(a) describe constitutional (structural) isomerism

(b) describe cis-trans isomerism in alkenes, and explain its origin in terms of restricted rotation due to the

presence of bonds

[use of E, Znomenclature is notrequired]

(c) explain what is meant by a chiral centre

(d) deduce whether a given molecule is chiral based on the presence or absence of chiral centres and/or aplane of symmetry

(e) recognise that an optically active sample rotates plane-polarised light and contains chiral molecules

(f) recognise that enantiomers have identical physical properties except in the direction in which they rotateplane-polarised light

[usage of the term diastereomers is notrequired]

(g) recognise that enantiomers have identical chemical properties except in their interactions with anotherchiral molecule

(h) recognise that different stereoisomers exhibit different biological properties, for example in drug action

(i) deduce the possible isomers for an organic molecule of known molecular formula

(j) identify chiral centres and/or cis-trans isomerism in a molecule of given structural formula

In each of the sections below, 11.3 to 11.8, candidates will be expected to be able to predict the reactionproducts of a given compound in reactions that are chemically similar to those specified.

11.3 Hydrocarbons

Content

Alkanes (exemplified by ethane)

(i) f di l b tit ti ti


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Learning Outcomes


(a) explain the general unreactivity of alkanes, including towards polar reagents

(b) describe the chemistry of alkanes as exemplified by the following reactions of ethane:

(i) combustion

(ii) free-radical substitution by chlorine and by bromine

(c) describe the mechanism of free-radical substitution with particular reference to the initiation,propagation and termination reactions

(d) explain the general reactivity of alkenes towards electrophilic reagents/electrophiles

(e) describe the chemistry of alkenes as exemplified, where relevant, by the following reactions of ethene:

(i) electrophilic addition of water/steam, hydrogen halides and halogens

(ii) reduction via catalytic hydrogenation (catalytic addition of hydrogen; see also 8(j))

(iii) oxidation by cold, alkaline solution of manganate(VII) ions to form the diol

(iv) oxidation by hot, acidified solution of manganate(VII) ions leading to the rupture of the

carbon-to-carbon double bond in order to determine the position of alkene linkages in largermolecules

(f) describe the mechanism of electrophilic addition in alkenes, using bromine with ethene as an example

(g) apply Markovnikovs rule to the addition of hydrogen halides to unsymmetrical alkenes, and explain thecomposition of products in terms of the stability of carbocation intermediates

(h) explain, in terms of delocalisation of electrons, the difference between benzene and alkene:

(i) reactivity towards electrophiles

(ii) preference of benzene to undergo substitution rather than addition reaction

(i) describe the chemistry of the benzene ring as exemplified by the following reactions of benzene andmethylbenzene:

(i) electrophilic substitution reactions with chlorine and with bromine

(recognise the use of Lewis acid as catalysts; see also Section 4)

(ii) nitration with concentrated nitric acid

(recognise concentrated sulfuric acid as a Brnsted-Lowry acid catalyst; see also Section 4)

(iii) Friedel-Crafts alkylation with halogenoalkanes

(recognise the use of Lewis acid as catalysts; see also Section 4)

(j) (i) describe the mechanism of electrophilic substitution in arenes, using the mono-bromination of


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(n) recognise the environmental consequences of:

(i) carbon monoxide, oxides of nitrogen and unburnt hydrocarbons arising from the internalcombustion engine and of their catalytic removal

(ii) gases that contribute to the enhanced greenhouse effect

(o) recognise that petroleum, a chemical feedstock, is a finite resource and the importance of recycling

11.4 Halogen Derivatives

Content

Halogenoalkanes

(i) nucleophilic substitution

(ii) elimination

Relative strength of the C-Hal bond

Unreactivity of halogenoarenes

Learning Outcomes


(a) recall the chemistry of halogenoalkanes as exemplified by:

(i) the following nucleophilic substitution reactions of bromoethane: hydrolysis; formation of nitriles;formation of primary amines by reaction with ammonia

(ii) the elimination of hydrogen bromide from 2-bromopropane

(b) describe and explain the mechanisms of nucleophilic substitutions in halogenoalkanes:(i) SN1, in terms of stability of the carbocation intermediates

(ii) SN2, in terms of steric hindrance of the halogenoalkanes

(c) explain the stereochemical outcome in nucleophilic substitution involving optically active substrates:

(i) inversion of configuration in SN2 mechanism

(ii) racemisation in SN1 mechanism

(d) interpret the different reactivities of halogenoalkanes, with particular reference to hydrolysis, and to therelative strengths of the C-Hal bonds

(e) explain the unreactivity of chlorobenzene compared to halogenoalkanes towards nucleophilicsubstitution, in terms of the delocalisation of the lone pair of electrons on the halogen and sterichindrance


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11.5 Hydroxy Compounds

Content

Alcohols (exemplified by ethanol)

(i) formation of halogenoalkanes

(ii) reaction with sodium; oxidation; dehydration

(iii) the tri-iodomethane test

Phenol

(i) its acidity; reaction with bases and sodium

(ii) nitration of, and bromination of, the aromatic ring

Learning Outcomes


(a) recall the chemistry of alcohols, exemplified by ethanol:

(i) combustion

(ii) nucleophilic substitution to give halogenoalkanes(iii) reaction with sodium

(iv) oxidation to carbonyl compounds and carboxylic acids

(v) dehydration to alkenes

(b) suggest characteristic distinguishing reactions for the different classes of alcohols (primary, secondaryand tertiary alcohols), e.g. mild oxidation

(c) deduce the presence of a CH3CH(OH) group in an alcohol from its reaction with alkaline aqueousiodine to form tri-iodomethane

(d) recall the chemistry of phenol, as exemplified by the following reactions:

(i) with bases

(ii) with sodium

(iii) nitration of, and bromination of, the benzene ring

(e) explain the relative acidities of water, phenol and ethanol in aqueous medium (interpret as Brnsted-Lowry acids)

11.6 Carbonyl Compounds

Content


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Learning Outcomes


(a) describe the formation of aldehydes and ketones from, and their reduction to, primary and secondaryalcohols respectively

(b) describe the mechanism of the nucleophilic addition reactions of hydrogen cyanide with aldehydes andketones

(c) explain the differences in reactivity between carbonyl compounds and alkenes towards nucleophilicreagents, such as lithium aluminium hydride and hydrogen cyanide

(d) describe the use of 2,4-dinitrophenylhydrazine (2,4-DNPH) to detect the presence of carbonylcompounds

(e) deduce the nature (aldehyde or ketone) of an unknown carbonyl compound from the results of simpletests (i.e. Fehlings and Tollens reagents; ease of oxidation)

(f) deduce the presence of a CH3CO group in a carbonyl compound from its reaction with alkalineaqueous iodine to form tri-iodomethane

11.7 Carboxylic Acids and Derivatives

Content

Carboxylic acids (exemplified by ethanoic acid and benzoic acid)

(i) formation from primary alcohols and nitriles

(ii) salt, ester and acyl chloride formation

Acyl chlorides (exemplified by ethanoyl chloride)(i) ease of hydrolysis compared with alkyl and aryl chlorides

(ii) reaction with alcohols, phenols and primary amines

Esters (exemplified by ethyl ethanoate and phenyl benzoate)

(i) formation from carboxylic acids and from acyl chlorides

(ii) hydrolysis (under acidic and under basic conditions)

Learning Outcomes


(a) describe the formation of carboxylic acids from alcohols, aldehydes and nitriles


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(g) describe the formation of esters from the condensation reaction of acyl chlorides, using phenyl benzoateas an example

(h) describe the acid and base hydrolysis of esters

11.8 Nitrogen Compounds

Content

Amines (exemplified by ethylamine and phenylamine)

(i) their formation

(ii) salt formation

(iii) other reactions of phenylamine

Amides (exemplified by ethanamide)

(i) formation from acyl chlorides

(ii) neutrality of amides

(iii) hydrolysis (under acidic and under basic conditions)

Amino acids (exemplified by aminoethanoic acid)

(i) their acid and base properties

(ii) zwitterion formation

Proteins

(i) formation of proteins

(ii) hydrolysis of proteins

Learning Outcomes


(a) describe the formation of amines as exemplified by ethylamine (through amide and nitrile reduction; seealso Section 11.4) and by phenylamine (through the reduction of nitrobenzene)

(b) describe the reaction of amines in the formation of salts

(c) describe and explain the basicity of primary, secondary and tertiary amines in the gaseous phase(interpret as Lewis bases)

(d) explain the relative basicities of ammonia, ethylamine and phenylamine in aqueous medium, in terms oftheir structures

(e) describe the reaction of phenylamine with aqueous bromine


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12. Electrochemistry

Content

Redox processes: electron transfer and changes in oxidation number (oxidation state) Electrode potentials

(i) standard electrode (redox) potentials, E; the redox series

(ii) standard cell potentials, E

cell, and their uses

(iii) batteries and fuel cells

Electrolysis

(i) factors affecting the amount of substance liberated during electrolysis

(ii) the Faraday constant; the Avogadro constant; their relationship

(iii) industrial uses of electrolysis

Learning Outcomes


(a) describe and explain redox processes in terms of electron transfer and/or of changes in oxidation

number (oxidation state)

(b) define the terms:

(i) standard electrode (redox) potential

(ii) standard cell potential

(c) describe the standard hydrogen electrode

(d) describe methods used to measure the standard electrode potentials of:

(i) metals or non-metals in contact with their ions in aqueous solution

(ii) ions of the same element in different oxidation states

(e) calculate a standard cell potential by combining two standard electrode potential

(f) use standard cell potentials to:

(i) explain/deduce the direction of electron flow from a simple cell

(ii) predict the spontaneity of a reaction

(g) understand the limitations in the use of standard cell potentials to predict the spontaneity of a reaction

(h) construct redox equations using the relevant half-equations (see also Section 13)

(i) state and apply the relationship G

= nFE

to electrochemical cells including the calculation of E


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(n) calculate:

(i) the quantity of charge passed during electrolysis

(ii) the mass and/or volume of substance liberated during electrolysis

(o) explain, in terms of the electrode reactions, the industrial processes of:

(i) the anodising of aluminium

(ii) the electrolytic purification of copper

[technical details are notrequired]

13. An Introduction to the Chemistry of Transition Elements

Content

General physical and characteristic chemical properties of the first set of transition elements, titanium tocopper

Colour of complexes

Learning Outcomes


(a) explain what is meant by a transition element, in terms of d block elements forming one or more stableions with partially filled d subshells

(b) state the electronic configuration of a first row transition element and its ions

(c) explain why atomic radii and first ionisation energies of the transition elements are relatively invariant

(d) contrast, qualitatively, the melting point and density of the transition elements with those of calcium as atypical s block element

(e) describe the tendency of transition elements to have variable oxidation states

(f) predict from a given electronic configuration, the likely oxidation states of a transition element

(g) describe and explain the use of Fe3+

/Fe2+

, MnO4/Mn

2+and Cr2O7

2/Cr

3+as examples of redox systems

(see also Section 12)

(h) predict, using Evalues, the likelihood of redox reactions

(i) define the terms ligandand complexas exemplified by the complexes of copper(II) ions with water,ammonia and chloride ions as ligands(including the transition metal complexes found in the Qualitative Analysis Notes)


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PRACTICAL ASSESSMENT

Scientific subjects are, by their nature, experimental. It is therefore important that, wherever possible, the

candidates carry out appropriate practical work to support the learning of this subject and to develop theexpected practical skills.

Paper 4 Practical

This paper is designed to assess a candidate's competence in those practical skills which can realistically beassessed within the context of a formal practical assessment.

Candidates will be assessed in the following skill areas:

(a) Planning (P)


define the question/problem using appropriate knowledge and understanding

give a clear logical account of the experimental procedure to be followed

describe how the data should be used in order to reach a conclusion

assess the risks of the experiment and describe precautions that should be taken to keep risks to aminimum

(b) Manipulation, measurement and observation (MMO)


demonstrate a high level of manipulative skills in all aspects of practical activity

make and record accurate observations with good details and measurements to an appropriate

degree of precision make appropriate decisions about measurements or observations

recognise anomalous observations and/or measurements (where appropriate) with reasonsindicated

(c) Presentation of data and observations (PDO)


present all information in an appropriate form

manipulate measurements effectively in order to identify trends/patterns

present all quantitative data to an appropriate number of decimal places/significant figures

(d) Analysis, conclusions and evaluation (ACE)


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One, or more, of the questions may incorporate some assessment of Skill P, set in the context of thesyllabus content, requiring candidates to apply and integrate knowledge and understanding from differentsections of the syllabus. It may also require the treatment of given experimental data to draw a relevantconclusion and analyse a proposed plan.

The assessment of skills MMO, PDO and ACE will also be set mainly in the context of the syllabus content.The assessment of PDO and ACE may also include questions on data-analysis which do not requirepractical equipment and apparatus.

Within the Scheme of Assessment, Paper 4 is weighted to 20% of the Higher 2 assessment. It is thereforerecommended that the schemes of work include learning opportunities that apportion a commensurateamount of time for the development and acquisition of practical skills. The guidance for practical work, whichis published separately, will provide examples of appropriate practical activities.

Candidates should be able to use appropriate apparatus/equipment to record a range of measurements suchas mass, time, volume and temperature. In addition, candidates are expected to have been exposed to arange of experimental techniques in the following areas:

1) Titration, e.g. acid-base titration (with suitable indicators such as methyl orange, screened methyl orange,thymolphthalein and thymol blue), redox titration, iodimetric titration, indirect titration, including thepreparation of standard solutions. Other types of titrations may also be required, where appropriate,sufficient working details will be given.

2) Gravimetric analysis, e.g. volatilisation gravimetry

3) Gas collection

4) Thermochemistry, including thermometric titration

5) Chemical kinetics, e.g. continuous and initial rate methods

6) Qualitative inorganic analysis involving an element, a compound or a mixture. Systematic analysis willnotbe required. Candidates should be familiar with the reactions of cations, reactions of anions andtest for gases as detailed in the Qualitative Analysis Notes.Reactions involving ions not included in the Qualitative Analysis Notes may be tested: in such cases,candidates will notbe expected to identify the ions but only to draw conclusions of a general nature.

Candidates should notattempt tests, other than those specified, on substances, except when it isappropriate to test for a gas.

7) Qualitative organic analysis requiring a knowledge of simple organic reactions as outlined in Section11.3 to 11.8, e.g. test-tube reactions indicating the presence of unsaturation (C=C), alcoholic,phenolic, carbonyl, carboxyl and amino groups, may be set, but this would be for the testing ofobservation skills and drawing general conclusions only.

8) Simple organic synthesis and purification, including use of water bath, setting up and use of reflux anddistillation apparatus.


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Apparatus List

This list given below has been drawn up in order to give guidance to Centres concerning the apparatus thatis expected to be generally available for examination purposes. The list is not intended to be exhaustive; in

particular, items (such as Bunsen burners, tripods) that are commonly regarded as standard equipment in achemical laboratory are not included.

Unless otherwise stated, the rate of allocation is per candidate.

two burettes, 50 cm3

two pipettes, 25 cm3

one pipette, 10 cm3

teat/dropping pipettes

one pipette fillertwo conical flasks within the range 150 cm3to 250 cm

3

third conical flask within the range 150 cm3to 250 cm

3, with suitable bung and delivery tube

tub suitable for acting as a trough (for collecting gas over water)volumetric flask, 250 cm

3

two measuring cylinders, 10 cm3

measuring cylinders, 25 cm3and 50 cm

3

two filter funnelstwo porcelain crucibles, approximately 15cm

3, with lids

one pipe-clay triangleone evaporating basin, at least 30cm3beakers, squat form with lip: 100 cm

3, 250 cm

3

thermometers: 10 C to +110 C at 1 C5 C to +50 C at 0.2 C

a polystyrene, or other plastic beaker of approximate capacity 150 cm3

test-tubes (Pyrex or hard glass), approximately 125 mm 15 mm

boiling tubes, approximately 150 mm 25 mmstopwatch to measure to an accuracy of about 1 s

balance, single-pan, direct reading, 0.01g or better (1 per 812 candidates)stand and clamp suitable for a burettewash bottle

The apparatus and material requirements for Paper 4 will vary year on year. Centres will be notified inadvance of the details of the apparatus and materials required for each practical examination.

Reagents

This list given below has been drawn up in order to give guidance to Centres concerning the standardreagents that are expected to be generally available for examination purposes. The list is not intended to beexhaustive and Centres will be notified in advance of the full list of all the reagents that are required for eachpractical examination.

aqueous sodium hydroxide (approximately 2 0 mol dm3

)


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SUMMARY OF KEY QUANTITIES AND UNITS

The list below is intended as a guide to the more important quantities which might be encountered in

teaching and used in question papers. The list is not exhaustive.

Quantity Usual symbols Unit

Base quantitiesamount of substance n mol

electric current I Alength l mmass m kg, g

thermodynamic temperature T Ktime t s

Other quantitiesacid dissociation constant Ka mol dm

3

atomic mass ma g, kgAvogadro constant L mol

1

base dissociation constant Kb mol dm3

bond energy kJ mol

1

charge on the electron e Cconcentration c mol dm3

density kg m3

, g dm3

, g cm3

electric potential difference V Velectromotive force E Velectron affinity kJ mol

1

enthalpy change of reaction H J, kJequilibrium constant K, Kp, Kc as appropriateFaraday constant F C mol

1

frequency v, f Hzhalf-life T, t sionic product, solubility product K, Ksp, as appropriateionic product of water Kw mol

2dm

6

ionisation energy I kJ mol1

lattice energy kJ mol

1

molar gas constant R J K1

mol1

molar mass M g mol

1

mole fraction x

molecular mass m g, kgneutron number N nucleon number A number of molecules N number of molecules per unit volume n m

3

order of reaction n, m partition coefficient K


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temperature , t Cvolume V, v m

3, dm

3

wavelength m, mm, nm


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MATHEMATICAL REQUIREMENTS

It is assumed that candidates will be competent in the techniques described below.

Make calculations involving addition, subtraction, multiplication and division of quantities.

Make approximate evaluations of numerical expressions.

Express small fractions as percentages, and vice versa.

Calculate an arithmetic mean.

Transform decimal notation to power of ten notation (standard form).

Use calculators to evaluate logarithms (for pH calculations), squares, square roots, and reciprocals.

Change the subject of an equation. (Most such equations involve only the simpler operations but mayinclude positive and negative indices and square roots.)

Substitute physical quantities into an equation using consistent units so as to calculate one quantity. Checkthe dimensional consistency of such calculations, e.g. the units of a rate constant k.

Solve simple algebraic equations.

Comprehend and use the symbols/notations , , /, , , x (or ).

Test tabulated pairs of values for direct proportionality by a graphical method or by constancy of ratio.

Select appropriate variables and scales for plotting a graph, especially to obtain a linear graph of the form

y= mx+ c.Determine and interpret the slope and intercept of a linear graph.

Choose by inspection a straight line that will serve as the least bad linear model for a set of data presentedgraphically.

Understand (i) the slope of a tangent to a curve as a measure of rate of change, (ii) the area below a curvewhere the area has physical significance, e.g. Boltzmann distribution curves.

Comprehend how to handle numerical work so that significant figures are neither lost unnecessarily nor usedbeyond what is justified.

Estimate orders of magnitude.Formulate simple algebraic equations as mathematical models, e.g. construct a rate equation, and identifyfailures of such models.

Calculators

Any calculator used must be on the Singapore Examinations and Assessment Board list of approvedcalculators.


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GLOSSARY OF TERMS

It is hoped that the glossary (which is relevant only to science subjects) will prove helpful to candidates as aguide, i.e. it is neither exhaustive nor definitive. The glossary has been deliberately kept brief not only withrespect to the number of terms included but also to the descriptions of their meanings. Candidates shouldappreciate that the meaning of a term must depend in part on its context.

1. Define (the term(s)...)is intended literally, only a formal statement or equivalent paraphrase beingrequired.

2. What do you understand by/What is meant by (the term(s)...) normally implies that a definition should begiven, together with some relevant comment on the significance or context of the term(s) concerned,especially where two or more terms are included in the question. The amount of supplementarycomment intended should be interpreted in the light of the indicated mark value.

3. State implies a concise answer with little or no supporting argument, e.g. a numerical answer that canbe obtained by inspection.

4. List requires a number of points, generally each of one word, with no elaboration. Where a givennumber of points is specified, this should not be exceeded.

5. Explain may imply reasoning or some reference to theory, depending on the context.

6. Describe requires candidates to state in words (using diagrams where appropriate) the main points ofthe topic. It is often used with reference either to particular phenomena or to particular experiments. Inthe former instance, the term usually implies that the answer should include reference to (visual)observations associated with the phenomena.

In other contexts, describe and give an account of should be interpreted more generally, i.e. thecandidate has greater discretion about the nature and the organisation of the material to be included inthe answer. Describe and explain may be coupled in a similar way to state and explain.

7. Discuss requires candidates to give a critical account of the points involved in the topic.

8. Outline implies brevity, i.e. restricting the answer to giving essentials.

9. Predict implies that the candidate is not expected to produce the required answer by recall but bymaking a logical connection between other pieces of information. Such information may be wholly givenin the question or may depend on answers extracted in an early part of the question.

10. Deduce is used in a similar way aspredict except that some supporting statement is required, e.g.reference to a law/principle, or the necessary reasoning is to be included in the answer.

11. Comment is intended as an open-ended instruction, inviting candidates to recall or infer points ofinterest relevant to the context of the question, taking account of the number of marks available.

12 S t i d i t i t t i ith t i l th t th i i ( i


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17. Estimate implies a reasoned order of magnitude statement or calculation of the quantity concerned,making such simplifying assumptions as may be necessary about points of principle and about thevalues of quantities not otherwise included in the question.

18. Sketch, when applied to graph work, implies that the shape and/or position of the curve need only bequalitatively correct, but candidates should be aware that, depending on the context, some quantitativeaspects may be looked for, e.g. passing through the origin, having an intercept, asymptote ordiscontinuity at a particular value.

In diagrams, sketch implies that a simple, freehand drawing is acceptable: nevertheless, care should betaken over proportions and the clear exposition of important details.

19. Construct is often used in relation to chemical equations where a candidate is expected to write abalanced equation, not by factual recall but by analogy or by using information in the question.

20. Compare requires candidates to provide both the similarities and differences between things orconcepts.

21. Classify requires candidates to group things based on common characteristics.

22. Recogniseis often used to identify facts, characteristics or concepts that are critical(relevant/appropriate) to the understanding of a situation, event, process or phenomenon.

TEXTBOOKS

Teachers may find reference to the following books helpful.

Cambridge International AS and A Level Chemistry by Peter Cann and Peter Hughes, published by HodderEducation

Cambridge International AS and A Level Chemistry Coursebook with CD-ROM (2nd Edition) by Lawrie Ryanand Roger Norris, published by Cambridge University Press

A Level Chemistry (4th Edition) by E. N. Ramsden, published by Oxford University Press

Understanding Chemistry for Advanced Level (3rd Edition), by Ted Lister and Janet Renshaw, published byOxford University Press

AS and A Level Chemistry through Diagrams by Michael Lewis, published by Oxford University Press

Chemistry in Context (6th Edition) by Graham Hill and John Holman, published by Oxford University Press

Chemistry in Context Laboratory Manual and Study Guide (5th Edition) by Graham Hill and John Holman,published by Oxford University Press

Experiments and Exercises in Basic Chemistry (7th Edition) by Steve Murov and Brian Stedjee, published byWiley


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for

Chemistry(Advanced Level)

For use in all papers, except practical examinations,for the H1, H2 and H3 Chemistry syllabuses


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Contents: Tables of Chemical data

1 Important values, constants and standards

2 Ionisation energies (1st, 2nd, 3rd and 4th) of selected elements in kJ mol1

3 Bond energies

4 Standard electrode potential and redox potentials, Eat 298 K (25 C)

5 Atomic and ionic radii

6 Typical proton (1H) chemical shift values () relative to TMS = 0

7 Characteristic infra-red absorption frequencies for some selected bonds

8 The orientating effect of groups in aromatic substitution reactions

9 Qualitative Analysis Notes

10 The Periodic Table of Elements


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1 Important values, constants and standards

molar gas constant R = 8.31 J K1

mol1

the Faraday constant F =9.65 104 C mol1

the Avogadro constant L = 6.02 1023

mol1

the Planck constant h =6.63 1034

J s

speed of light in a vacuum c = 3.00 108m s

1

rest mass of proton, 11

H mp= 1.67 1027

kg

rest mass of neutron,0

1n mn= 1.67 10

27kg

rest mass of electron, e0

1 me= 9.11 10

31kg

electronic charge e =1.60 1019

C

molar volume of gas Vm= 22.7 dm3mol1at s.t.p.Vm= 24 dm

3mol

1at r.t.p.

(where s.t.p. is expressed as 105Pa [1 bar] and 273 K [0 C],

r.t.p. is expressed as 101325 Pa [1 atm] and 293 K [20 C])

ionic product of waterKw= 1.00 10

14mol

2dm

6

(at 298 K [25 C])

specific heat capacity of water

= 4.18 kJ kg1

K1

(= 4.18 J g1K1)


2 I i ti i (1 t 2 d 3 d d 4th) f l t d l t i kJ l1

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2 Ionisation energies (1st, 2nd, 3rd and 4th) of selected elements, in kJ mol 1

Proton Number First Second Third Fourth

H 1 1310

He 2 2370 5250

Li 3 519 7300 11800

Be 4 900 1760 14800 21000

B 5 799 2420 3660 25000

C 6 1090 2350 4610 6220

N 7 1400 2860 4590 7480

O 8 1310 3390 5320 7450

F 9 1680 3370 6040 8410

Ne 10 2080 3950 6150 9290

Na 11 494 4560 6940 9540

Mg 12 736 1450 7740 10500

Al 13 577 1820 2740 11600

Si 14 786 1580 3230 4360

P 15 1060 1900 2920 4960

S 16 1000 2260 3390 4540

Cl 17 1260 2300 3850 5150

Ar 18 1520 2660 3950 5770

K 19 418 3070 4600 5860

Ca 20 590 1150 4940 6480

Sc 21 632 1240 2390 7110


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Proton Number First Second Third Fourth

Zn 30 908 1730 3828 5980

Ga 31 577 1980 2960 6190

Ge 32 762 1540 3300 4390

Br 35 1140 2080 3460 4850

Rb 37 403 2632 3900 5080

Sr 38 548 1060 4120 5440

Ag 47 731 2074 3361

Sn 50 707 1410 2940 3930

I 53 1010 1840 3200 4030

Cs 55 376 2420 3300

Ba 56 502 966 3390

Pb 82 716 1450 3080 4080


3 Bond energies

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3 Bond energies

3(a) Bond energies in diatomic molecules (these are exact values)

Homonuclear Heteronuclear

Bond Energy/kJ mol1

Bond Energy/kJ mol1

HH 436 HF 562

DD 442 HCl 431

NN 944 HBr 366

O=O 496 HI 299

FF 158 CO 1077

ClCl 244

BrBr 193

II 151


3(b) Bond energies in polyatomic molecules (these are average values)

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3(b) Bond energies in polyatomic molecules (these are average values)

Homonuclear Heteronuclear

Bond Energy/kJ mol1

Bond Energy/kJ mol1

CC 350 CH 410

C=C 610 CF 485

CC 840 CCl 340

C C (benzene) 520 CBr 280

NN 160 CI 240

N=N 410 CN 305

OO 150 C=N 610

SiSi 222 CN 890

PP 200 CO 360

SS 264 C=O 740

C=O in CO2 805

NH 390

NCl 310

OH 460

SiCl 359

SiH 320

SiO (in SiO2(s)) 460

Si=O (in SiO2(g)) 640

PH 320

PCl 330


4 Standard electrode potential and redox potentials, E

at 298 K (25o

C)

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4 Standard electrode potential and redox potentials, E at 298 K (25 C)

For ease of reference, two tabulations are given:(a) an extended list in alphabetical order;(b) a shorter list in decreasing order of magnitude, i.e. a redox series.

4(a)Ein alphabetical order

Electrode reaction E/ V

Ag++ e

Ag +0.80

Al3+

+ 3e

Al 1.66

Ba2+

+ 2e Ba 2.90

Br2+ 2e

2Br +1.07

Ca2+

+ 2e

Ca 2.87

Cl2+ 2e

2Cl

+1.36

2HOCl+ 2H++ 2e

Cl2 + 2H2O +1.64

ClO+ H2O + 2e

Cl

+ 2OH

+0.81

Co2+

+ 2e

Co 0.28

Co3++ e Co2+ +1.89

[Co(NH3)6]2+

+ 2e

Co + 6NH3 0.43

Cr2+

+ 2e

Cr 0.91

Cr3+

+ 3e

Cr 0.74

Cr3+

+ e

Cr2+

0.41

Cr2O72

+ 14H++ 6e

2Cr

3++ 7H2O +1.33

C+

+ e

C +0 52


Electrode reaction E

/ V

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Fe3+

+ e

Fe2+

+0.77

[Fe(CN)6]3+ e [Fe(CN)6]

4 +0.36

Fe(OH)3+ e

Fe(OH)2+ OH 0.56

2H++ 2e

H2 0.00

I2+ 2e 2I

+0.54

K++ e

K 2.92

Li++ e

Li 3.04

Mg2+

+ 2e

Mg 2.38

Mn2+

+ 2e

Mn 1.18

Mn3+

+ e

Mn2+

+1.54

MnO2+ 4H++ 2e

Mn

2++ 2H2O +1.23

MnO4+ e

MnO4

2 +0.56

MnO4+ 4H

++ 3e

MnO2+ 2H2O +1.67

MnO4+ 8H

++ 5e

Mn

2++ 4H2O +1.52

NO3+ 2H

++ e

NO2+ H2O +0.81

NO3+ 3H

++ 2e

HNO2+ H2O +0.94

NO3

+ 10H

+

+ 8e

NH4+

+ 3H2O +0.87

Na++ e

Na 2.71

Ni2+

+ 2e

Ni 0.25



/ V

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Electrode reaction E / V

O2+ H2O + 2e

HO2+ OH

0.08

2H2O + 2e H2+ 2OH

0.83

Pb2+

+ 2e

Pb 0.13

Pb4+

+ 2e

Pb2+

+1.69

PbO2+ 4H++ 2e

Pb

2++ 2H2O +1.47

SO42

+ 4H++ 2e

SO2+ 2H2O +0.17

S2O82

+ 2e

2SO42

+2.01

S4O62

+ 2e

2S2O32

+0.09

Sn2+

+ 2e

Sn 0.14

Sn4+

+ 2e

Sn2+

+0.15

V2+

+ 2e

V 1.20

V3+

+ e

V2+

0.26

VO2+

+ 2H++ e

V

3++ H2O +0.34

VO2++ 2H

++ e

VO

2++ H2O +1.00

VO3+ 4H

++ e

VO

2++ 2H2O +1.00

Zn2+

+ 2e

Zn 0.76

All ionic states refer to aqueous ions but other state symbols have been omitted.


4(b)Ein decreasing order of oxidising power

( )

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(a selection only see also the extended alphabetical list on the previous pages)


F2+ 2e 2F

+2.87

S2O82

+ 2e 2SO4

2 +2.01

H2O2+ 2H++ 2e

2H2O +1.77

MnO4

+ 8H

+

+ 5e

Mn

2+

+ 4H2O +1.52

PbO2+ 4H++ 2e

Pb

2++ 2H2O +1.47

Cl2+ 2e 2Cl

+1.36

Cr2O72

+ 14H++ 6e

2Cr

3++ 7H2O +1.33

O2+ 4H++ 4e 2H2O +1.23

Br2+ 2e 2Br

+1.07

ClO+ H2O + 2e

Cl

+ 2OH

+0.81

NO3+ 10H

++ 8e

NH4

++ 3H2O +0.87

NO3+ 2H

++ e

NO2+ H2O +0.81

Ag++ e

Ag +0.80

Fe3+

+ e Fe

2+ +0.77

I2+ 2e

2I

+0.54

O2+ 2H2O + 4e 4OH

+0.40

Cu2+

+ 2e Cu +0.34



/ V

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Electrode reaction E / V

Fe2+

+ 2e Fe 0.44

Zn2+

+ 2e Zn 0.76

2H2O + 2e H2+ 2OH

0.83

V2+

+ 2e V 1.20

Mg2+

+ 2e Mg 2.38

Ca2+

+ 2e Ca 2.87

K++ e

K 2.92


5 Atomic and ionic radii

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(a) Period 1 atomic/nm ionic/nm

single covalent H 0.037 H

0.208

van der Waals He 0.140

(b) Period 2

metallic Li 0.152 Li+ 0.060

Be 0.112 Be+

0.031

single covalent B 0.080 B3+

0.020

C 0.077 C4+

0.015 C4

0.260

N 0.074 N3

0.171

O 0.073 O2

0.140

F 0.072 F 0.136

van der Waals Ne 0.160

(c) Period 3

metallic Na 0.186 Na+ 0.095

Mg 0.160 Mg+

0.065

Al 0.143 Al +

0.050

single covalent Si 0.117 Si4+

0.041

P 0.110 P3

0.212

S 0.104 S2

0.184

Cl 0.099 Cl 0.181

van der Waals Ar 0.190


(e) Group 14 atomic/nm ionic/nm

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single covalent C 0.077

Si 0.117 Si4+

0.041

Ge 0.122 Ge2+

0.093

metallic Sn 0.162 Sn2+

0.112

Pb 0.175 Pb2+

0.120

(f) Group 17

single covalent F 0.072 F 0.136

Cl 0.099 Cl 0.181

Br 0.114 Br 0.195

I 0.133 I

0.216

At 0.140

(g) First row d block elements

metallic Sc 0.164 Sc +

0.075

Ti 0.146 Ti2+

0.086 Ti3+

0.067

V 0.135 V2+

0.079 V3+

0.064

Cr 0.129 Cr2+

0.073 Cr3+

0.062

Mn 0.132 Mn2+

0.083 Mn3+

0.058

Fe 0.126 Fe2+

0.061 Fe3+

0.055

Co 0.125 Co2+

0.065 Co3+

0.055

Ni 0.124 Ni2+

0.069 Ni3+

0.056

Cu 0.128 Cu2+ 0.073

Zn 0.135 Zn+

0.074


6 Typical proton (1H) chemical shift values () relative to TMS = 0

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Type ofproton

Environment of proton Example structuresChemical Shift

range ()

CH

alkane CH3, CH2, 0.91.7

alkyl next to C=O CH3C=O, CH2C=O, 2.23.0

alkyl next to aromatic ring CH3Ar, CH2Ar, 2.33.0

alkyl next toelectronegative atom

CH3O, CH2O, CH2Cl,

3.24.0

attached to alkyne CH 1.83.1

attached to alkene =CH2, =CH 4.56.0

attached to aromatic ring 6.09.0

aldehyde 9.310.5

OH(see note

below)

alcohol ROH 0.56.0

phenol 4.57.0

carboxylic acid 9.013.0

alkyl amine RNH 1.05.0

aryl amine 3 0 6 0


7 Characteristic infra-red absorption frequencies for some selected bonds

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BondFunctional groups containing

the bondAbsorption range (inwavenumbers) / cm

1

Appearance of peak(s = strong,

w = weak)

CCl chloroalkanes 700800 s

CO alcoholetherestercarboxylic acids

9701260100013101050133012101440

ssss

C=C aromaticalkenes

1475162516351690

sw

C=O amidesketones and aldehydescarboxylic acidsesters

16401690167017401680173017101750

ssss

CC alkynes 21502250 wunless conjugated

CN nitriles 22002250 w

CH alkanes, CH2H

alkenes/arenes, =CH

2850295030003100

sw

NH amines, amides 33003500 w

OH carboxylic acid, RCO2H

H-bonded alcohol/phenol, ROHfree alcohol, ROH

25003000

3200360035803650

sand very broad

ssand shape


8 The orientating effect of groups in aromatic substitution reactions

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The position of the incoming group, E, is determined by the nature of the group, G, already bonded to the

ring, and not by the nature of the incoming group E.

G

alkylOH or ORNH2, NHR or NR2NHCOR

Cl, Br, I

CHO, CORCO2H, CO2RNH3

+

NO2, CN

Reactivity of ring(compared to

benzene)Activated Deactivated Deactivated

Position of E(relative to position

of G)2- and/or 4- 2- and/or 4- 3-


9 Qualitative Analysis Notes[ppt. = precipitate]

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9(a) Reactions of aqueous cations

cationreaction with

NaOH(aq) NH3(aq)

aluminium,Al

3+(aq)

white ppt.soluble in excess

white ppt.insoluble in excess

ammonium,

NH4+

(aq)ammonia produced on heating

barium,Ba

2+(aq)

no ppt.(if reagents are pure)

no ppt.

calcium,Ca

2+(aq)

white. ppt. with high[Ca

2+(aq)]

no ppt.

chromium(III),Cr3+(aq)

grey-green ppt.

soluble in excessgiving dark green solution

grey-green ppt.insoluble in excess

copper(II),Cu

2+(aq),

pale blue ppt.insoluble in excess

blue ppt.soluble in excessgiving dark blue solution

iron(II),Fe

2+(aq)

green ppt., turning brown oncontact with air

insoluble in excess

green ppt.,turning brown oncontact with air

insoluble in excess

iron(III),Fe

3+(aq)

red-brown ppt.insoluble in excess

red-brown ppt.insoluble in excess

magnesium,Mg

2+(aq)



manganese(II),Mn2+(aq)

off-white ppt., rapidly turning

brown on contact with airinsoluble in excess

off-white ppt., rapidly turning

brown on contact with airinsoluble in excess

zinc,Zn

2+(aq)




9(b) Reactions of anions

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anion reaction

carbonate,CO3

2 CO2liberated by dilute acids

chloride,Cl

(aq)

gives white ppt. with Ag+(aq) (soluble in NH3(aq))

bromide,Br

(aq)

gives pale cream ppt. with Ag+(aq) (partially soluble in NH3(aq))

iodide,I(aq)

gives yellow ppt. with Ag+(aq) (insoluble in NH3(aq))

nitrate,NO3

(aq)

NH3liberated on heating with OH(aq) and Alfoil

nitrite,NO2

(aq)

NH3liberated on heating with OH(aq) and Alfoil;

NO liberated by dilute acids

(colourless NO (pale) brown NO2 in air)

sulfate,SO4

2(aq)

gives white ppt. with Ba2+

(aq) (insoluble in excess dilute strong acids)

sulfite,SO3

2(aq)

SO2liberated with dilute acids;gives white ppt. with Ba

2+(aq) (soluble in dilute strong acids)

9(c) Tests for gases

gas test and test result

ammonia, NH3 turns damp red litmus paper blue

carbon dioxide, CO2gives a white ppt. with limewater(ppt. dissolves with excess CO2)

chlorine, Cl2 bleaches damp litmus paper

hydrogen, H2 pops with a lighted splint

oxygen, O2 relights a glowing splint

10 The Periodic Table of Elements

Group

1 2 13 14 15 16 17 18

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Key 1

Hhydrogen

1.0

2

Hehelium

4.0

3

Lilithium

6.9

4

Beberyllium

9.0

atomic number

atomic symbolname

relative atomic mass

5

Bboron

10.8

6

Ccarbon

12.0

7

Nnitrogen

14.0

8

Ooxygen

16.0

9

Ffluorine

19.0

10

Neneon

20.2

11

Nasodium

23.0

12

Mgmagnesium

24.3 3 4 5 6 7 8 9 10 11 12

13

Alaluminium

27.0

14

Sisilicon

28.1

15

Pphosphorus

31.0

16

Ssulfur

32.1

17

Clchlorine

35.5

18

Arargon

39.9

19

Kpotassium

39.1

20

Cacalcium

40.1

21

Scscandium

45.0

22

Tititanium

47.9

23

Vvanadium

50.9

24

Crchromium

52.0

25

Mnmanganese

54.9

26

Feiron

55.8

27

Cocobalt

58.9

28

Ninickel

58.7

29

Cucopper

63.5

30

Znzinc

65.4

31

Gagallium

69.7

32

Gegermanium

72.6

33

Asarsenic

74.9

34

Seselenium

79.0

35

Brbromine

79.9

36

Krkrypton

83.8

37

Rbrubidium

85.5

38

Srstrontium

87.6

39

Yyttrium

88.9

40

Zrzirconium

91.2

41

Nbniobium

92.9

42

Momolybdenum

95.9

43

Tctechnetium

44

Ruruthenium

101.1

45

Rhrhodium

102.9

46

Pdpalladium

106.4

47

Agsilver

107.9

48

Cdcadmium

112.4

49

Inindium

114.8

50

Sntin

118.7

51

Sbantimony

121.8

52

Tetellurium

127.6

53

I

iodine

126.9

54

Xexenon

131.3

55

Cscaesium

132.9

56

Babarium

137.3

5771

lanthanoids

72

Hfhafnium

178.5

73

Tatantalum

180.9

74

Wtungsten

183.8

75

Rerhenium

186.2

76

Ososmium

190.2

77

Iriridium

192.2

78

Ptplatinum

195.1

79

Augold

197.0

80

Hgmercury

200.6

81

Tlthallium

204.4

82

Pblead

207.2

83

Bibismuth

209.0

84

Popolonium

85

Atastatine

86

Rnradon

87

Frfrancium

88

Raradium

89103

actinoids

104

Rfrutherfordium

105

Dbdubnium

106

Sgseaborgium

107

Bhbohrium

108

Hshassium

109

Mtmeitnerium

110

Dsdarmstadtium

111

Rgroentgenium

112

Cncopernicium

114

Flflerovium

116

Lvlivermorium

lanthanoids

57

Lalanthanum

138.9

58

Cecerium

140.1

59

Prpraseodymium

140.9

60

Ndneodymium

144.2

61

Pmpromethium

62

Smsamarium

150.4

63

Eueuropium

152.0

64

Gdgadolinium

157.3

65

Tbterbium

158.9

66

Dydysprosium

162.5

67

Hoholmium

164.9

68

Ererbium

167.3

69

Tmthulium

168.9

70

Ybytterbium

173.1

71

Lulutetium

175.0

actinoids

89

Acactinium

90

Ththorium

232.0

91

Paprotactinium

231.0

92

Uuranium

238.0

93

Npneptunium

94

Puplutonium

95

Amamericium

96

Cmcurium

97

Bkberkelium

98

Cfcalifornium

99

Eseinsteinium

100

Fmfermium

101

Mdmendelevium

102

Nonobelium

103

Lrlawrencium

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