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1
CHEMISTRY SYLLABUS OUTLINE
(republished 2012 edition)
Note: SPECIAL THANKS to the following for pointing out
errors that were present in previous versions:
Mrs Felicia Wong and Pham Thang Loi (VS 4D 2011)
Lim Ting Jie
VS Class of 2011
2
SECTION I: EXPERIMENTAL CHEMISTRY
1. Experimental Chemistry
Description Content Years tested
1.2 Methods of purification and analysis
(a) (ii) Sublimation
Inverted funnel with a wet cloth on the sides over the heated evaporating dish
Separates solid that is able to change its state to gas directly without becoming a liquid from solid that is unable to decompose when heated
-
(a) (iii) Distillation (and fractional distillation)
The liquid, with a lower boiling point, will boil to become a gas and pass through the Liebig condenser to be condensed and collected as liquid in the beaker
Separates liquid from the solid dissolved in it
(Separates liquids of differing boiling points that are misible with a fractionating column of glass beads)
2006^
(b) Paper chromatography
Spot of the mixture of different compounds is applied to pencil marking of paper, its end thereafter dipped in ethanol
Ethanol that is soaked up by the paper dissolves the dyes and carries them up the chromatography paper
More soluble dyes will be carried further up, higher Rf value
2007
SECTION II: ATOMIC STRUCTURE AND STOICHIOMETRY
2. The Particulate Nature of Matter
Description Content Years tested
2.1 Kinetic particle theory
(a) (i) Solid state Closely packed in a regular pattern
Vibrate about fixed positions
2007
(a) (ii) Liquid state Closely packed in a disorderly manner
Move randomly and slide over one another
(a) (iii) Gaseous state Spread far apart in a disorderly manner
Move randomly and rapidly
(b) Evidence for movement of particles in fluids
Fluids have no fixed shape
Particles are not held in fixed positions
Have high kinetic energy and able to move about
-
(d) (i) Effect of molecular mass on the rate of diffusion
Gas A has a higher molecular mass than Gas B
Heavier than Gas B
Requires more energy to move it to another place
Diffuses at a slower rate
2003, 2010
(d) (ii) Effect of temperature on rate of diffusion
Gas A is at a higher temperature than Gas B
Posses greater kinetic energy than Gas B
Diffuses at a faster rate
-
2.3 Structure and properties of materials
(b) (i) Low mbps. of simple molecular subs.
Weak intermolecular forces between the molecules
Little energy needed to break them
2003, 2004, 2006^
(b) (ii) Inability to conduct electricity of simple molecular subs.
All electrons bonded in the neutral molecules
No mobile ions or electrons free to move in conduction
2003, 2008
(b) (iii) High melting and boiling points of tetrahedral giant molecular substances
Atoms held together by strong covalent bonds
Tetrahedral and three-dimensional network
Large amounts of energy needed to break strong bonds
2004
3
Description Content Years tested
2.3 Structure and properties of materials
(b) (iii) Inability to conduct electricity of tetrahedral giant molecular substances
Each atom covalently bonded to 4 other atoms
All electrons are used in bonding
No free mobile electrons able to move about to conduct electricity
-
(b) (iii) Hard and abrasive properties of tetrahedral giant molecular substances
Atoms held together by strong covalent bonds
Rigid structure of tetrahedral network
Large amounts of energy needed to distort arrangement
2004^
(b) (iv) High mbps of parallel giant molecular substances
Atoms held together by strong covalent bonds
Within their layers
Much energy needed to break strong bonds
-
(b) (iv) Ability to conduct electricity of parallel giant molecular substances
Each atom covalently bonded to 3 other atoms instead of 4
Each consists of an electron not used for bonding
Free to move about and conduct electricity
2008
(b) (iv) Lubricative property of parallel giant molecular substances
Carbon atoms in hexagonal layers
Layers held by weak van der Waal’s forces of attraction
Small amount of energy needed for layers to slide past one other
-
2.4 Ionic bonding
(e) High melting and boiling points of ionic compounds
Giant lattice network of positive and negative ions
Strong electrostatic forces of attraction
Large amounts of energy needed to overcome
2002, 2006
(e) Electrical conductivity of ionic compounds
Giant lattice network of positive and negative ions
Strong electrostatic forces of attraction
Ions held strongly in fixed positions
Not free to move about during conducting
2006^
(e) Electrical conductivity of ionic compounds as when molten (or aqueous)
Original giant lattice structure when solid collapses
Ions not held strongly in fixed positions any longer
Free to move about during conducting of electricity
2006^, 2007
2.6 Metallic bonding
(b) Electrical conductivity of metals to the structure
Sea of delocalised valence electrons are mobile
Free to move from negative terminal to positive terminal in electrical circuit
2003, 2006^
SECTION IV: PERIODICITY
8. The Periodic Table
Description Content Years tested
(a) Group I metals decreases in melting point (and increases in reactivity) with water down the group
Bigger atomic size
Outershell electron further away from nucleus
Less energy needed to break the weaker electrostatic force of attraction metallic bond between outershell electron and positive nuclei
(Easier to lose an electron)
-
(b) (i) Group VII halogens changes in state from gas to solid downwards
Molecular size increases
Stronger intermolecular forces of attraction
More energy needed to break the forces
Higher melting (liquid-solid) and boiling (gas-liquid) points
-
(b) (ii) Group VII halogens decrease in displacement reactivity with other halide ion solutions downwards
Bigger atomic size
Outershell electron further away from nucleus
Weaker electrostatic force of attraction to nucleus
Harder to gain an electron
2002
4
SECTION III: CHEMISTRY OF REACTIONS
4. Electrolysis
Description Content Years tested
(c) Electrolysis of molten sodium chloride (as an example)
Positive metal ion discharged and attracted to negative cathode
Metal atoms form a (white) metallic coating around the cathode
Negative ion discharged and attracted to positive anode
The (yellowish green) gas is formed
2004
(e) (i) (a) Selective discharge of cations in dilute electrolytes
Cation in the electrolyte is lower in the reactivity series than hydrogen ion of water
Less reactive
Preferentially discharged instead of hydrogen ion
Intensity of colour of electrolyte decreases and turns lighter (in cases of transition metals)
2009
(e) (i) (b) Selective discharge of cations in concentrated electrolytes
Cation in the electrolyte is lower in the reactivity series than carbon (of inert electrode)
Less reactive
Preferentially discharged instead of hydrogen ion
Intensity of colour of electrolyte decreases and turns lighter (in cases of transition metals)
-
(e) (ii) Selective discharge of cations in concentrated electrolytes
The non-polyatomic ion in the electrolyte is more reactive than hydroxide ion of water
Easier to be discharged and preferentially discharged instead
As hydrogen ions become greater in concentration than hydroxide ions,
Electrolyte turns more acidic
(e) (iii) (a) Selective discharge of hydrogen ions in dilute electrolytes
Hydrogen ion of the water is lower in the reactivity series than cation in the electrolyte
Less reactive and preferentially discharged instead of the cation
As hydroxide ions become greater in concentration than hydrogen ions,
Electrolyte turns more alkaline
-
(e) (iii) (b) Selective discharge of hydroxide ions in dilute electrolytes
Hydroxide ion is found in greater concentrations than anion in the electrolyte
Easier to be discharged and preferentially discharged instead
As hydrogen ions become greater in concentration than hydroxide ions,
Electrolyte turns more acidic
-
(i) Electroplating of metals and uses
Depositing a layer of metal on another substance using electrolysis
Make a cheap metal look more expensive with silver or gold
Protect a metallic object from corrosion with tin or chrome
-
(j) Electrical energy from redox reactions of simple cells
Oxidation occurs at less reactive electrode and reduction occurs at the more reactive electrode
Electrons are transferred from the more reactive electrode to the less reactive through the wire
These moving electrons in the external circuit constitute electric current
2008^
(j) Differences of electrical energy with different metals
Metal A is further away from Metal B in the reactivity series than it is from Metal C
Difference in their reactivities is higher
Greater voltage produced
2004
(k) Possible changes in electrolytes
Decrease in intensity of colour of aqueous salt in electrolyte
Changes in pH value
Changes in colour of solution by discharge of negative ions to form liquid
Metallic coating present at the cathode
Volume of molten electrolyte
2003, 2008
5
5. Energy from Chemicals
Description Content Years tested
(d) (i) Enthalpy changes in exothermic reactions
Heat energy released in covalent bond forming of Product B is greater than that absorbed in covalent bond breaking of the Reactant A
Moles of products and types of bonds included
2002
(d) (ii) Enthalpy changes in a endothermic reaction
Heat energy absorbed in covalent bond breaking of the Reactant A is greater than that released in covalent bond forming of Product B
Moles of products and types of bonds included
2009
(e) (i) Hydrogen and oxygen to generate electricity in a fuel cell
At positive cathode, oxygen gas is reduced to form hydroxide ions
At negative anode, hydrogen gas is oxidised to form water
The flow of electrons constitute electric current generating electricity
2009
Cathode Anode Overall
O2 + 2 H2O + 4e → 4 OH- 2 H2 + 4 OH- → 4 H2O + 4e O2 + 2 H2 → 2 H2O
(e) Hydrogen a potential fuel
Renewable source of energy and pollution free, water only product
But costly to obtain pure hydrogen and difficult to store
Also, less energy per volume than petrol
-
6. Chemical Reactions
Description Content Tested
6.1 Speed of reaction
(a) (i) Decreased concentration decreases rates of reactions
Particles A are further apart from one another
Less reactant particles per unit volume
Collisions between Particles A and B occur at a less frequent rate, resulting in less effective collisions
2003
(a) (ii) Increased pressure increases rates of reactions
Total volume of gas decreases
Particles A are squeezed closer together
More reactant particles per unit volume
Collisions between Particles A and B occur at a more frequent rate, resulting in more effective collisions
2002
(a) (iii) Decreased particle size increases rates of reactions
Higher surface area of Particles A are exposed to that of Particles B
Likelihood of collision of Particles A and B increases
Collisions between Particles A and B occur at a more frequent rate, resulting in more effective collisions
2007
(a) (iv) Increased temperature increases rates of reactions
Higher kinetic energy is resulted in the Particles A
Particles A are move faster
Collisions between Particles A and B occur at a more frequent rate, resulting in more effective collisions
-
(b) Effects of catalysts
Increases (alters) rate of a chemical reaction without itself being chemically changed and without any change in mass
-
(c) Pathways with lower activation energies
Catalysts provide an alternate reaction pathway with lower activation energy compared to the original reaction
More reacting particles can overcome the activation energy for reaction per unit time
2006, 2010
(e) Method for investigating effect of given variables
Using an electronic balance, cotton wool and conical flask for mass loss
Using a calibrated gas syringe, stopper and conical flask for increase in specific gases
2003, 2007, 2010
Note: You must state the names of the particles.
Ionic compounds can be either soluble or insoluble.
If soluble we refer to the particles as <name> ions,
but if insoluble we refer to them as, simply, <name> particles.
covalent bonding referred as <name> molecules.
metallic bonding referred as <name> metal atoms.
6
7. Acids, Bases and Salts
Description Content Years tested
7.1 Acids and bases
(c) (i) Strong and weak acids
Strong acids ionise fully in water to produce a high concentration of hydrogen ions irreversibly
Weak acids ionise partially in water to product a low concentration of hydrogen reversibly
2004, 2008, 2010^
(c) (ii) Comparing strong acids
Hydrochloric acid is monobasic while sulfuric acid is dibasic
Sulfuric acid has one more hydrogen atom replaceable by a metal than hydrochloric acid
Ionises more fully in water and reacts faster with reactants
2005
(g) Control of soil pH with calcium hydroxide
Calcium hydroxide is alkaline and react with acids to neutralise excess acidity by acid rain in soil
Excessive liming with result in excess alkalinity
React with ammonium fertilisers to form ammonia gas resulting in loss of nitrogen, a nutrient element essential for plant growth
2005, 2007^, 2009
7.2 Salts
(a) (i) Reactions with acids to prepare soluble salts (due to anion)
React acid with excess insoluble reactant
Filter the resulting solution to obtain filtrate containing the soluble salt in beaker
Heat the filtrate until saturated and allow it to cool
Wash with little cold distilled water and dry between pieces of filter paper
2004
(a) (iii) Pre-titration to prepare Group I/ammonium salts (cation)
Pipette 25 cm3 of alkali into the conical flask
Add a few drops of methyl orange
Titrate acid from burette into the beaker drop wise until solution turns from yellow to orange.
Note difference in initial and final reading of burette as X
-
(a) (iii) Main titration to prepare Group I/ammonium salts (cation)
Pipette 25 cm3 of alkali into a beaker
Titrate X volume of acid into it
Heat the filtrate until saturated and allow it to cool
Wash with little cold distilled water and dry between pieces of filter paper
2004
(a) (ii) Precipitation to prepare insoluble salts
React the aqueous solutions together
Filter the resulting solution to obtain residue in the filter paper
Wash with much distilled water and dry between pieces of filter paper
2004^
(i) (i) Acidic oxides
Contains an non-metal (usually forming a dioxide or higher with oxygen e.g. SO2)
Can react with alkali to form a salt and water to form an acid
-
(i) (ii) Amp-hoteric oxides
Oxides of Zn, Al, Pb (ZAP)
Can react with both acids and alkalis to form salt and water -
(i) (iii) Basic oxides
‘Metal oxides that are not amphotheric’
Can react with acid to form a salt and water if soluble to form an alkali
2010
(i) (iv) Neutral oxides
Contains an non-metal (usually forming a monoxide with oxygen e.g. H2O)
Unable to react with acids nor alkalis
-
7
SECTION IV: PERIODICITY
9. Metals
Description Content Years tested
9.1 Properties of metals
(a) (i) High mbps of metals that are not from Group I
Strong electrostatic force of attraction between positive ions and delocalised sea of electrons.
Large amount of energy is needed to break the strong metallic bonds
2003^
(a) (ii) Physical property of metals as being malleable
Equally sized atoms are orderly arranged.
Each electron does not belong to any particular ion
Metallic bonds will not be broken if positive metal ions are displaced
Applied force can cause layers to slide over each other easily
2003^
(a) (iii) Metals are good conductors of heat
Sea of delocalised valance electrons are mobile
Free to move rapidly across metal surface
Carrying heat energy with it at the same time
-
(a) (iv) Metals are good conductors of electricity
Sea of delocalised valence electrons are mobile
Free to move from negative terminal to positive terminal in electrical circuit
2003, 2005
(d) Alloys have different physical properties to their constituent elements
Alloys are harder than the constituent element
Atoms of another element added have a different size from that of the pure metal
Regular arrangement of atoms in the pure metal is disrupted
Atoms of differing sizes cannot slide over one another as easily as before
2007, 2010
9.3 Extraction of metals
(a) (i) Ease of obtaining metals from CO3
2- and OH- ores
Only carbonates/hydroxides of metals of lower reactivities between Calcium and Copper in the reactivity series can decompose to form its metal oxides
Carbonates of metals of higher reactivities are more thermally stable and hence does not decompose
2002
(a) (ii) Ease of obtaining metals from oxide ores
Only oxides of metals of lower reactivities between Mercury and Platinum in the reactivity series can decompose to form their respective metals
Oxides of metals of higher reactivities are more thermally stable and hence does not decompose
-
(a) (iii) Ease of obtaining metals from decomposition of their compounds in general
Metal A in metal oxide/carbonate A is more reactive than Metal B in metal oxide/carbonate B
It is more thermally stable hence more difficult for Metal A to be extracted from its oxide/carbonate by decomposition compared to Metal B
Rate of decomposition is slower
2004, 2010^
9.4 Recycling of metals
(a) Metals need to be recycled
Metal ores are finite resources
Recycling will decrease the space needed for landfills required to dispose metals, hence decreasing land pollution
2002, 2004
9.5 Iron
(d) Prevention of rusting to be achieved
Painting, plastic coating, greasing, galvanising (zinc-plating)
Protective layer of substance
Prevents water and air from coming into contact with surface
Not all conditions for rusting present
2005^, 2007
(e) Sacrificial protection of a metal by a more reactive metal
Metal A is higher in reactivity series
More reactive and loses electrons more readily than Metal B
Oxidised by air and water in preference to Metal B
Metal B offers sacrificial protection to other metal and hence corrodes preferentially
2002, 2006
8
SECTION V: ATMOSPHERE
10. Air
Description Content Years tested
(c) (i) state the source of carbon monoxide
Incomplete combustion under limited oxygen supply
Carbon-containing substances like petroleum
Forms instead of carbon dioxide in complete combustion
2009
(c) (ii) state the source of nitrogen oxides
High temperatures from lightning activity and internal combustion engines
Provide enough energy to break the triple covalent bonds between nitrogen atoms of nitrogen gas in air
Each nitrogen atom reacts with oxygen
-
(c) (iii) state the source of sulfur dioxide
Volcanic eruptions and
Combustion of fossil fuels form sulfur gas
Sulfur atoms react with oxygen
-
(d) (i) describe solutions to problems from carbon monoxide and nitrogen monoxide
Catalytic converters
Platinum and rhodium catalysts
Less or non harmful carbon dioxide and nitrogen gas
By redox reactions
-
(d) (ii) describe solutions to problems from unburnt hydrocarbons
Catalytic converters of platinum and rhodium catalysts
Less or non harmful carbon dioxide and water vapour
By redox reactions
2004^
(d) (iii) describe solutions to problems from sulfur dioxide
Flue gas desulfurisation plant
Calcium carbonate reacts with sulfur dioxide to form calcium sulfite and carbon dioxide gas
Calcium sulfite oxidised by oxygen in air to form calcium sulfate
-
(e) (i) discuss effects of carbon monoxide
Reacts more readily with haemoglobin of red blood cells than oxygen does
Stable carboxyhaemoglobin compound forms
Red blood cells unable to transport blood around body efficiently
Dizziness and death likely to result
2002, 2004, 2010
(e) (ii) discuss effects of nitrogen oxides and sulfur dioxide
High levels will cause inflammation of lungs, bronchitis
Dissolve in rainwater and oxidise in air to form nitric and sulfuric acids in rain
Vegetation soil leached and marine habitats polluted
Corrodes buildings made of metal and carbonates
2006^, 2010
(f) (i) discuss importance of the ozone layer
Filter UV radiation
Genetic mutations causing eye cataracts and skin cancer
Harm to marine life
2002, 2006
(f) (ii) discuss problems involved with the depletion of ozone
Aerosol propellants that force out contents and coolants in refrigerators expel chlorofluorocarbons
Stable and diffuse in air easily
React with ozone under sunlight
2006^
(h) give the sources of carbon dioxide
Respiration of organisms
Combustion of carbon-containing fuels -
(h) give the sources of methane
Bacterial decomposition and decay of vegetation, animals and rubbish
2007
(h) discuss possible consequences of global warming
Higher temperatures will melt icebergs at the North and South poles, flooding lowlands and coastal areas
Decreases crop yields with droughts in dry countries from higher temperatures
2002, 2007, 2010
9
SECTION VI: ORGANIC CHEMISTRY
11. Organic Chemistry
Description Content Years tested
11.1 Fuels and crude oil
(b) Fractional distillation of petroleum
Petroleum heated into a vapour is pumped into fractionating column
Hot vapour rises up and cools
Larger hydrocarbons of higher boiling points condense lower in the column, while smaller ones of lower boiling points condense higher in the column
2004
(e) Issues of competing uses of oil as an energy source and as a chemical feedstock
Petroleum in a non-renewable energy source.
Hydrocarbons when combusted produces greenhouse gas carbon dioxide causing global warming
Sulfur dioxide from coal and petroleum causes acid rain and soot is also produced
-
11.2 Alkanes
(a) (i) Homologous series
Group of organic compounds with a general formula of ____
Similar chemical properties differing only by CH2 units
2009, 2010
(a) (ii) Increase in melting and boiling points
Increase in molecular size and mass
Intermolecular forces between molecules increase
More energy required to break the forces
2005^, 2006
(a) (iii) Increase in viscosity
Increase in molecular size and mass
Intermolecular forces between molecules increase
Flows less easily and more resistant to flow
-
(a) (iv) Gradation in flammability (less) and sootiness (more)
Increase in molecular size and mass
Higher percentage of carbon
Less flammable and harder to burn
Smokier and sootier flame
-
11.3 Alkenes
(c) Purpose of cracking
Match the higher demand for fractions containing shorter chained hydrocarbon as smaller molecules from the refinery process
11.5: Carboxylic acids
(f) Commercial uses of esters
Perfumes (sweet and fruity, colourless and insoluble)
Flavourings (soluble in organic solvents)
Solvents (soluble in organic solvents)
2010
11.6 Macromolecules
(a) (i) Macromolecules
Large molecules built up from small units by covalent bonds
Different macromolecules having different units and/or different linkages
2009
(a) (ii) Monomers and polymers
A small molecule that can be joined together to form a large molecule known as a polymer
A long-chain molecule made up of many small molecules, known as monomers, joined together
2009, 2010
(a) (iii) Addition and condensation polymersation
Process of joining together monomer units to form a macromolecule
A - Without losing any molecules or atoms
C - With a small molecule as a by-product
2007, 2008
(f) Typical uses of man-made fibres
Clothing, parachutes, fishing line, sleeping bags
Easier to wash and dry
Long lasting as they do not shrink or crease
2005
(g) Problems by disposal of non-biodegradable plastics
Non-biodegradable plastics being long lasting (hence high in demand) cannot be decomposed by bacteria
Pollution by permanently being present at landfills
More space needed for landfills
2005^, 2008
10
CONTENT W/O KEY WORDS OVERVIEW (refer to Chem Syllabus Quick References)
SECTION I: EXPERIMENTAL CHEMISTRY
1. Experimental Chemistry
1.1 Experimental design
(b) suggest suitable apparatus, given relevant information, for a variety of simple experiments, including collection of
gases and measurement of rates of reaction
1.2 Methods of purification and analysis
(a) describe methods of separations and purification
(i) use of a suitable solvent, filtration and crystallisation or evaporation
(b) (ii) interpret chromatograms including comparison with ‘known’ samples and the use of Rf values
(d) deduce from the given melting point and boiling point the identities of substances and their purity
(e) explain that the measurement of purity in substances used in everyday life, e.g. foodstuffs and drugs, is
important
1.3 Identification of ions and gases
(a) describe the use of aqueous sodium hydroxide and aqueous ammonia to identify the aqueous cations SAPAZCLCII
(b) describe tests to identify the anions NCSCI
(c) describe tests to identify the gases ACSCHO
SECTION II: ATOMIC STRUCTURE AND STOICHIOMETRY
2. The Particulate Nature of Matter
2.2 Atomic structure
(a) state the relative charges and approximate relative masses of a proton, a neutron and an electron
(b) describe, with the aid of diagrams, the structure of an atom as containing protons and neutrons (nucleons) in the
nucleus and electrons arranged in shells (energy levels)
(c) define proton (atomic) number and nucleon (mass) number
(e) define the term isotopes
(f) deduce the numbers of protons, neutrons and electrons in atoms and ions given proton and nucleon numbers
2.3 Structure and properties of materials
(a) describe the differences between elements, compounds and mixtures
(b) name some simple molecular substances, e.g. methane; iodine and giant molecular substances, e.g. poly(ethene);
sand (silicon dioxide); diamond; graphite
(d) deduce the physical and chemical properties of substances from their structures and bonding and vice versa
11
2.4 Ionic bonding
(a) describe the formation of ions by electron loss/gain in order to obtain the electronic configuration of a noble gas
(b) describe the formation of ionic bonds between metals and non-metals, e.g. NaCl; MgCl2
(c) state that ionic materials contain a giant lattice in which the ions are held by electrostatic attraction, e.g. NaCl
(d) deduce the formulae of other ionic compounds from diagrams of their lattice structures, limited to binary
compounds
2.5 Covalent bonding
(a) describe the formation of a covalent bond by the sharing of a pair of electrons in order to gain the electronic
configuration of a noble gas
(b) describe, using ‘dot-and-cross’ diagrams, the formation of covalent bonds between nonmetallic elements, e.g. H2;
O2; H2O; CH4; CO2
(c) deduce the arrangement of electrons in other covalent molecules
2.6 Metallic bonding
(a) describe metals as a lattice of positive ions in a ‘sea of electrons’
3. Formulae, Stoichiometry and the Mole Concept
(a) state the symbols of the elements and formulae of the compounds mentioned in the syllabus
(b) deduce the formulae of simple compounds from the relative numbers of atoms present and vice versa
(c) deduce the formulae of ionic compounds from the charges on the ions present and vice versa
(d) interpret chemical equations with state symbols
(e) construct chemical equations, with state symbols, including ionic equations
(f) define relative atomic mass, Ar
(g) define relative molecular mass, Mr, and calculate relative molecular mass (and relative formula mass) as the sum
of relative atomic masses
(h) calculate the percentage mass of an element in a compound when given appropriate information
(i) calculate empirical and molecular formulae from relevant data
(j) calculate stoichiometric reacting masses and volumes of gases (one mole of gas occupies 24 dm3) at room
temperature and pressure); calculations involving the idea of limiting reactants may be set
(k) apply the concept of solution concentration (in mol/dm3 or g/dm3) to process the results of volumetric
experiments and to solve simple problems
(l) calculate % yield and % purity
12
SECTION III: CHEMISTRY OF REACTIONS
4. Electrolysis
(a) describe electrolysis as the conduction of electricity by an ionic compound (an electrolyte), when molten or
dissolved in water, leading to the decomposition of the electrolyte
(b) describe electrolysis as evidence for the existence of ions which are held in a lattice when solid but which are free
to move when molten or in solution
(g) construct ionic equations for the reactions occurring at the electrodes during the electrolysis, given relevant
information
5. Energy from Chemicals
(a) describe the meaning of enthalpy change in terms of exothermic (ΔH negative) and endothermic (ΔH positive)
reactions
(b) represent energy changes by energy profile diagrams, including reaction enthalpy changes and activation
energies (see 6.1(c),6.1(d))
6. Chemical Reactions
6.1 Speed of reaction
(d) state that some compounds act as catalysts in a range of industrial processes and that enzymes are biological
catalysts
(f) interpret data obtained from experiments concerned with speed of reaction
6.2 Redox
(a) define oxidation and reduction (redox) in terms of oxygen/hydrogen gain/loss
(b) define redox in terms of electron transfer and changes in oxidation state
(c) identify redox reactions in terms of oxygen/hydrogen gain/loss, electron gain/loss and changes in oxidation state
(d) describe the use of aqueous potassium iodide and acidified potassium dichromate(VI) in testing for oxidising and
reducing agents from the resulting colour changes
7. Acids, Bases and Salts
7.1 Acids and bases
(a) describe the meanings of the terms acid and alkali in terms of the ions they produce in aqueous solution and their
effects on Universal Indicator
(b) describe how to test hydrogen ion concentration and hence relative acidity using Universal Indicator and the pH
scale
(d) describe the characteristic properties of acids as in reactions with metals, bases and carbonates
(e) state the uses of sulfuric acid in the manufacture of detergents and fertilisers; and as a battery acid
(f) describe the reaction between hydrogen ions and hydroxide ions to produce water, H+ + OH- → H2O, as
neutralisation
13
(h) describe the characteristic properties of bases in reactions with acids and with ammonium salts
(j) classify sulfur dioxide as an acidic oxide and state its uses as a bleach, in the manufacture of wood pulp for paper
and as a food preservative (by killing bacteria)
7.2 Salts
(b) describe the general rules of solubility for common salts to include nitrates, chlorides (including silver and lead),
sulfates (including barium, calcium and lead), carbonates, hydroxides, Group I cations and ammonium salts
7.3 Ammonia
(a) describe the use of nitrogen, from air, and hydrogen, from cracking oil, in the manufacture of ammonia
(b) state that some chemical reactions are reversible, e.g. manufacture of ammonia
(c) describe the essential conditions for the manufacture of ammonia by the Haber process
(d) describe the displacement of ammonia from its salts
SECTION IV: PERIODICITY
8. The Periodic Table
8.1 Periodic trends
(a) describe the Periodic Table as an arrangement of the elements in the order of increasing proton (atomic) number
(b) describe how the position of an element in the Periodic Table is related to proton number and electronic
structure
(c) describe the relationship between group number and the ionic charge of an element
(d) explain the similarities between the elements in the same group of the Periodic Table in terms of their electronic
structure
(e) describe the change from metallic to non-metallic character from left to right across a period of the Period Table
(f) describe the relationship between group number, number of valency electrons and metallic/non-metallic
character
(g) predict the properties of elements in Group I and VII using the Periodic Table
8.2 Group properties
(a) describe lithium, sodium and potassium in Group I (the alkali metals) as a collection of relatively soft, low density
metals
(b) describe chlorine, bromine and iodine in Group VII (the halogens) as a collection of diatomic non-metals
(c) describe the elements in Group 0 (the noble gases) as a collection of monatomic elements that are chemically
unreactive and hence important in providing an inert atmosphere, e.g. argon and neon in light bulbs; helium in
balloons; argon in the manufacture of steel
(d) describe the lack of reactivity of the noble gases in terms of their electronic structures
14
9. Metals
9.1 Properties of metals
(b) describe alloys as a mixture of a metal with another element, e.g. brass; stainless steel
(c) identify representations of metals and alloys from diagrams of structures
9.2 Reactivity series
(a) place in order of reactivity calcium, copper, (hydrogen), iron, lead, magnesium, potassium, silver, sodium and zinc
by reference to their reactions (SAW) and the reduction of their oxides (CH)
(b) describe the reactivity series as related to the tendency of a metal to form its positive ion, illustrated by its
reaction with the aqueous ions and/or oxides of the other listed metals
(c) deduce the order of reactivity from a given set of experimental results
(d) describe the action of heat on the carbonates of the listed metals and relate thermal stability to the reactivity
series
9.4 Recycling of metals
(b) discuss the social, economic and environmental issues of recycling metals
9.5 Iron
(a) describe and explain the essential reactions in the extraction of iron using haematite, limestone and coke in the
blast furnace
(b) describe steels as alloys which are a mixture of iron with carbon or other metals and how controlled use of these
additives changes the properties of the iron, e.g. high carbon steels are strong but brittle whereas low carbon steels
are softer and more easily shaped
(c) state the uses of mild steel, e.g. car bodies; machinery, and stainless steel, e.g. chemical plants; cutlery; surgical
instruments
SECTION V: ATMOSPHERE
10. Air
(a) describe the volume composition of gases present in dry air as being approximately 79% nitrogen, 20% oxygen
and the remainder being noble gases (with argon as the main constituent) and carbon dioxide
(b) name some common atmospheric pollutants, e.g. carbon monoxide; methane; nitrogen oxides (NO and NO2);
ozone; sulfur dioxide; unburned hydrocarbons
(g) describe the carbon cycle in simple terms, to include
(i) the processes of combustion, respiration and photosynthesis
(ii) how the carbon cycle regulates the amount of carbon dioxide in the atmosphere
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SECTION VI: ORGANIC CHEMISTRY
11. Organic Chemistry (excluding key reactions and drawing of the four main structure types)
11.1 Fuels and crude oil
(a) name natural gas, mainly methane, and petroleum as sources of energy
(b) describe petroleum as a mixture of hydrocarbons and its separation into useful fractions by fractional distillation
(c) name the following fractions and state their uses
(i) petrol (gasoline) as a fuel in cars (iv) diesel as a fuel for diesel engines
(ii) naphtha as feedstock for the chemical industry
(iii) paraffin (kerosene) as a fuel for heating and cooking and for aircraft engines
(v) lubricating oils as lubricants and as a sources of polishes and waxes (vi) bitumen for making road surfaces
(d) state that the naphtha fraction from crude oil is the main source of hydrocarbons used as the feedstock for the
production of a wide range of organic compounds
11.2 Alkanes
(d) define isomerism and identify isomers
(e) describe the properties of alkanes (exemplified by methane) as being generally unreactive
11.3 Alkenes
(a) describe the alkenes as an homologous series of unsaturated hydrocarbons
(c) recognise that cracking is essential to match the demand for fractions containing smaller molecules from the
refinery process
(d) describe the difference between saturated and unsaturated hydrocarbons from their molecular structures
(f) state the meaning of polyunsaturated when applied to food products
11.4 Alcohols
(e) state some uses of ethanol, e.g. as a solvent; as a fuel; as a constituent of alcoholic beverages
11.5 Carboxylic acids
(c) describe the carboxylic acids as weak acids, reacting with carbonates, bases and some metals
11.6 Macromolecules
(b) describe the formation of poly(ethene) as an example of addition polymerisation of ethene as the monomer
(c) state some uses of poly(ethene) as a typical plastic, e.g. plastic bags; clingfilm
(d) deduce the structure of the polymer product from a given monomer and vice versa
(e) describe nylon, a polyamide, and Terylene, a polyester, as condensation polymers, the partial structure of nylon
being represented and the partial structure of Terylene