Edexcel GCSE Chemistry A (1530) 

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C1: Classifying materials

Atomic structure
You should be able to:
C1.01 describe the structure of an atom as a nucleus containing protons and neutrons, surrounded by orbiting electrons arranged in shells
C1.02 recall the relative mass and relative charge of a proton, a neutron and an electron
C1.03 understand the terms atomic number, mass number and relative atomic mass
C1.04 describe the electronic structures of the first twenty elements in the periodic table in terms of numbers of electrons in electron shells, given the atomic numbers
C1.05 explain the existence of isotopes
C1.06 calculate the relative atomic mass of an element from relative masses and abundances of its isotopes

Bonding
You should be able to:
C1.07 understand that atoms of different elements can combine to form compounds by the formation of new chemical bonds
C1.08 understand that ionic bonds can be made by the transfer of electrons to form cations and anions
C1.09 describe the formation of Na ⁺ and Cl ^- ions and hence the formation of ions in other ionic compounds from their atoms
C1.10 describe and explain the physical properties of giant ionic structures, including sodium chloride and magnesium oxide
C1.11 understand that covalent bonds can be made by electron sharing to form molecules
C1.12 describe the formation, including dot and cross diagrams, of simple molecules including H₂, HC1, H₂O and CO₂
C1.13 describe and explain the physical properties of simple molecular substances ideas
C1.14 understand that covalent bond formation can also result in giant structures including diamond and graphite  
C1.15 describe and explain the physical properties of giant covalent structures including diamond and graphite
C1.16explain the difference between properties of simple molecular substances and giant covalent substances 

C2: Changing materials - formulae and equations

Representing reactions
You should be able to:
C2.01represent chemical reactions by word equations
C2.02 recall the formulae of elements and simple compounds in the specification
C2.03 calculate relative formula mass from relative atomic masses
C2.04 write simple balanced equations
C2.05 use the state symbols (s), (l), (g) and (aq)
C2.06 write balanced equations to describe and explain a wide range of reactions including ionic equations and those occurring in electrolytic cells
C2.07 determine the formulae of simple compounds from reacting masses and understand that these are empirical
C2.08 use chemical equations to calculate masses of reactants and products

C3: Patterns of behaviour - in elements and compounds

The periodic table
You should be able to:
C3.01 recall that there are approximately 100 elements and that all materials are composed of one or more of these
C3.02 understand that the periodic table shows elements in order of increasing atomic number, arranged in rows (periods)
C3.03 recall that elements with similar properties appear in the same vertical column (group)
C3.04 recall the positions of the alkali metals (group 1), the halogens (group 7), the noble gases (group 0) and the transition metals in the periodic table
C3.05 understand the connection between the number of outer electrons and the position of an element in the periodic table
C3.06 understand that the reactions of elements depend upon the arrangement of electrons in their atoms
C3.07 recall that there is a gradual change in the properties of the elements from the top to the bottom of each group

Noble gases
You should be able to:
C3.08 relate the uses of noble gases to their physical properties and lack of chemical reactivity
C3.09 explain the monatomic nature of noble gases

Alkali metals
You should be able to:
C3.10 recall that the alkali metals have comparatively low melting points and boiling points and are softer than other metals
C3.11 describe the relative reactivity of the alkali metals as exemplified by their reaction with water
C3.12 recall that common compounds of the alkali metals are soluble in water and that the oxides and hydroxides of the alkali metals are alkaline (pH>7)

Halogens
You should be able to:
C3.13 recall the colours and physical states of the halogens at room temperature
C3.14 recall that halogens react with metals to form metal halides
C3.15 recall that halogens react with hydrogen to produce hydrogen halides which dissolve in water to form acidic solutions (pH<7)
C3.16 describe the relative reactivity of the halogens as exemplified by their displacement reactions with halide ions in aqueous solution
C3.17 describe the use of fluorides in the water supply and in toothpaste, of chlorine in water purification and of iodine as an antiseptic

Chemicals from salt
You should be able to:
C3.21 recall that hydrogen, chlorine and sodium hydroxide are produced by the electrolysis of concentrated aqueous sodium chloride and know how to test for these substances
C3.22 describe the uses of sodium chloride, hydrogen, chlorine and sodium hydroxide

Chemicals from calcium carbonate
You should be able to:
C3.23 describe the thermal decomposition of calcium carbonate to make calcium oxide and carbon dioxide
C3.24 describe the effect of water on calcium oxide and appreciate that the solution produced is lime water
C3.25 understand why calcium oxide and calcium hydroxide are used to neutralise soil acidity
C3.26 recall that calcium carbonate is used in the production of glass, cement and iron

C4: Changing materials - useful products

Extraction and uses of metals
You should be able to:
C4.01 define oxidation in terms of gain of oxygen and reduction in terms of loss of oxygen
C4.02 define oxidation in terms of loss of electrons and reduction in terms of gain of electrons
C4.03 understand that the extraction of metals involves reduction of their ores
C4.04 recall how the way in which a particular metal is extracted from its ores is related to its position in the reactivity series
C4.05 understand that processes involving the use of large amounts of electricity are relatively expensive
C4.06describe the extraction of aluminium from purified bauxite including simple cell diagram, nature of electrolyte and electrodes, and reactions
C4.07 relate the uses of aluminium to its properties
C4.08 recall that carbon and carbon monoxide can reduce the oxides of less reactive metals
C4.09 describe the extraction of iron in the blast furnace, including outline diagram, raw materials, reactions and the formation and uses of slag
C4.10 describe the purification of copper by electrolysis, including a simple diagram of the cell

Useful products from crude oil
You should be able to:
C4.11 recall that hydrocarbons contain carbon and hydrogen only and that crude oil is a mixture of hydrocarbons
C4.12 describe the fractional distillation of crude oil
C4.13 understand that the larger the hydrocarbon molecule, the higher the boiling point of the hydrocarbon and the less volatile it is at a given temperature
C4.14 recall the uses of the main fractions (gases, petrol, naphtha, kerosene, diesel oil, fuel oil, bitumen)
C4.15 recall and explain the formation of the products of the complete and incomplete combustion (oxidation) of hydrocarbons, and the possible effect of these on the environment
C4.16 describe how to test for carbon dioxide (using lime water) and water (using cobalt chloride)
C4.17 explain that cracking involves the breaking down of larger hydrocarbon molecules into smaller, more useful ones, some of which have carbon-carbon double bonds
C4.18 describe the conditions used in industry to crack fractions obtained from crude oil
C4.19 recall that, when alkanes are cracked, mixtures of alkanes and alkenes are formed
C4.20 explain that alkanes are saturated hydrocarbons and that alkenes are unsaturated hydrocarbons 
C4.21 recall that methane is the main constituent of natural gas
C4.22 recall the formulae of methane, ethane, propane and butane (not methylpropane) and draw the structures of these molecules
C4.23 recall the formulae of ethene and propene and draw the structures of their molecules
C4.24describe how bromine water is used to distinguish between alkanes and alkenes
C4.25 recall that polymers are large molecules which can be formed by a combination of many smaller molecules
C4.26 explain how addition polymers are formed from unsaturated monomers (equations required)
C4.27describe the uses and associated properties of poly(ethene), poly(propene) and poly(chloroethene)

C5: Patterns of behaviour - in reactions

Rates of reaction
You should be able to:
C5.01 recall that the rates of chemical reactions vary from very fast, explosive reactions to very slow reactions which form no detectable products
C5.02 describe experiments to investigate the effect of temperature, concentration and surface area of a solid on the rate of a reaction
C5.03 interpret the results of such experiments
C5.04 recall and explain the effect of changes in temperature, concentration and surface area of a solid on a given rate of reaction
C5.05 understand that reactions can occur when particles collide and that increasing the frequency and energy of collisions increases the rate of the reaction
C5.06 describe the effect of a catalyst on a given rate of reaction
C5.07 define enzymes as catalysts in biological systems and describe their use in washing powder, and food and drink manufacture 
C5.08 describe how the rates of enzyme-catalysed reactions vary with temperature and pH

Energy transfers accompanying reactions
You should be able to:
C5.09 recall that changes of temperature often accompany reactions
C5.10 define an exothermic reaction as one in which heat energy is given out, and give examples
C5.11 define an endothermic reaction as one in which heat energy is taken in, and give examples
C5.12 recall that the breaking of bonds is endothermic and that the making of bonds is exothermic

C6: Changing materials - the environment

Manufacture of ammonia and fertilisers
You should be able to:
C6.01 describe the conditions under which ammonia is produced from nitrogen and hydrogen in the Haber process
C6.02 understand that this reaction is reversible and may reach a dynamic equilibrium
C6.03 understand how the position of a dynamic equilibrium is affected by changes of temperature and pressure, to include the Haber process as an example
C6.04 understand the consequential effects of these changes on the rate of attainment of equilibrium and the need to use a catalyst
C6.05 recall that a nitrogenous fertiliser is manufactured by neutralising ammonia with nitric acid
C6.06 recall that nitrogenous fertilisers promote plant growth
C6.07 understand that the process of leaching of artificial fertilisers causes excessive plant growth in rivers and lakes and may be harmful to health

The Earth and its atmosphere
You should be able to:
C6.08 describe the composition of the atmosphere
C6.09 understand that the Earth’s early atmosphere was probably formed from the gases produced by volcanic activity
C6.10 recall that originally the atmosphere probably contained a large amount of carbon dioxide together with water vapour, hydrogen, nitrogen and carbon monoxide
C6.11 explain the origin of the oceans by condensation of water vapour and describe how the percentage of carbon dioxide in the atmosphere was consequently reduced
C6.12 explain that the first primitive plants released oxygen as a result of photosynthesis and that the percentage of oxygen in the atmosphere gradually increased
C6.13 explain how the carbon cycle helps to maintain atmospheric composition, ie carbon dioxide is added to the atmosphere by respiration and combustion and removed by photosynthesis and dissolving in water
C6.14 understand that the crystalline nature of igneous rocks and the fact that they do not contain fossils are evidence for their formation from hot, molten magma
C6.15 understand that crystal size in igneous rocks depends on the rate of cooling
C6.16 understand that the presence of fossils in a rock is evidence that it has been formed from sediments
C6.17 understand that in sedimentary rocks the deepest layers are usually the oldest, that sedimentary rocks may contain fossils, and that the type of fossil can help to date the rocks
C6.18 explain how metamorphic rocks are formed by the action of heat and pressure on existing rocks
C6.19 understand that metamorphic rocks having the same composition as other rocks is evidence for their formation from these rocks – eg marble and limestone are both calcium carbonate

C7: Preparing and analysing

Solubility of salts
You should be able to:
C7.01 recall the general rules which describe the solubility of common types of salt in water:
- all common sodium, potassium and ammonium salts are soluble
- all nitrates are soluble
- all common ethanoates are soluble
- common chlorides are soluble except those of silver and lead
- common sulfates are soluble except those of lead, barium and calcium
- common carbonates and hydroxides are insoluble except those of sodium, potassium and ammonium
C7.02 use solubility information and knowledge of the methods of preparation of salts to predict and explain a suitable method for the preparation of pure solid samples of salts
C7.03 understand that insoluble salts can be formed as precipitates by the reaction of suitable reagents in solution
C7.04 describe and understand the preparation of pure, dry samples of insoluble salts

Titration
You should be able to:
C7.05 understand the need to use titration to determine the exact amount of a soluble reactant which reacts with an acid when preparing some soluble salts
C7.06 recall the procedure for carrying out simple acid-base titrations using burette, pipette and suitable indicators

Collection and identification of gases
You should be able to:
C7.07 understand how to collect gases by upward and downward delivery, over water and using a gas syringe
C7.08 recall how to collect and how to test for hydrogen, oxygen, ammonia, carbon dioxide, hydrogen chloride and sulfur dioxide
C7.09 appreciate the potential hazards when hydrogen, ammonia, hydrogen chloride and sulfur dioxide are collected or used

Tests for ions
You should be able to:
C7.10 understand that precipitation reactions form the basis of some tests for ions
C7.11 recall the tests for the following ions in solids or solutions as appropriate:
H⁺ using acid/base indicators and typical acid reactions
Na⁺, K⁺, Ca²⁺, Cu²⁺ using flame tests
Al³⁺, Ca²⁺, Cu²⁺, Fe²⁺, Fe³⁺, NH₄+ using sodium hydroxide solution
CO₃^2- using dilute acid and identifying the carbon dioxide evolved
SO₃^2-  using dilute hydrochloric acid and identifying the sulfur dioxide evolved
SO₄^2- using dilute hydrochloric acid and barium chloride solution
Cl^-, Br^-, I^- using dilute nitric acid and silver nitrate solution
OH^- using acid/base indicators and reaction when heated with an ammonium salt
C7.12 explain, and write equations for, the ionic reactions involved in these tests

Hard water
You should be able to:
C7.13 define hard water as water which does not readily lather with soap but gives scum
C7.14 appreciate that hard water wastes soap but does not affect soapless detergents and recall that dissolved calcium and magnesium salts cause hardness
C7.15 understand that hardness results from contact with limestone, chalk and gypsum
C7.17 understand industrial and domestic problems caused by depostion of scale
C7.18 understand that the presence of hardness in water causes the inner surface of pipework to become coated, which prevents corrosion and the entry of poisonous salts of copper or lead into the water supply
C7.19 describe the treatment of water to make it suitable for domestic use, including the need for sedimentation, filtration and chlorination

Quantitative chemistry
You should be able to:
C7.20 recall Avogadro’s Law and use it to calculate volumes of gases in reactions, given the relevant equation
C7.21 convert moles into masses and vice versa
C7.22 calculate the volume of a given mass of gas (given the molar volume at the appropriate temperature and pressure) and vice versa
C7.23 calculate and interrelate masses or volumes of substances involved in a reaction, given the relevant equation
C7.24 convert mass-concentration into mol dm^-3 and vice versa
C7.25 perform simple calculations from the results of titration

C8 Industrial and organic chemistry

Making metals useful
You should be able to:
C8.01 understand why aluminium is less reactive than expected and appreciate how anodising is achieved and the change that takes place during the process
C8.02 appreciate the need for alloying aluminium to increase its strength
C8.03 understand the important uses of aluminium and its alloys
C8.04 explain the chemical reactions occurring in different parts of the blast furnace and the energy changes associated with them
C8.05 understand that impure iron from the blast furnace and pure iron have very limited uses
C8.06 describe the production of mild steel by lowering the carbon content in the impure iron using high pressure oxygen
C8.07 understand the uses of mild steel
C8.08 understand the uses of alloy steels such as stainless steel, titanium steel and manganese steel

Sulfuric acid
You should be able to:
C8.09 recall and explain the manufacture of sulfuric acid from sulfur and sulfide ores
C8.10 explain the operating conditions used in the Contact process
C8.11 recall some uses of sulfuric acid to illustrate its economic importance

Organic chemistry
You should be able to:
C8.12 understand how ethanol is produced during the fermentation of carbohydrates and how to obtain a concentrated solution of ethanol by fractional distillation of the fermentation mixture
C8.13 recall that ethanol is also produced by hydration of ethene
C8.14 evaluate the factors which are relevant to the choice of method to be used in the manufacture of ethanol, eg the relative availability of sugar cane and crude oil
C8.15 understand that different amounts of ethanol are present in various drinks
C8.16 appreciate the social issues and possible harmful effects of ethanol in alcoholic drinks
C8.17recall that industrial methylated spirit contains ethanol with added methanol to make it unfit to drink
C8.18 describe the use of ethanol as a solvent and as a fuel
C8.19 recall that ethanol can be oxidised to form ethanoic acid and that this reaction occurs in wine in an open bottle
C8.20 understand that ethanoic acid is a typical acid, reacting with indicators and with metals, bases and carbonates to form ethanoate salts
C8.21 recall that ethanoic acid is present in vinegar, which is used as a flavouring and as a preservative
C8.22 recall that ethanol reacts with ethanoic acid to produce an ester, ethyl ethanoate C8.23 describe esters as sweet-smelling substances which are present in flavourings (eg pear-drops) and perfumes
C8.24 define homologous series and understand that alkanes, alkenes, alcohols and carboxylic acids are examples of such series
C8. 25 recall the names, formulae and structures of the first four members of each of these series (excluding secondary and tertiary alcohols)
C8.26 understand that members of a homologous series show a gradual variation in physical properties as exemplified by their boiling points
C8.27 explain that the alcohols have similar chemical properties as exemplified by their combustion and esterification reactions
C8.28 recall the formulae of esters formed from the acids and alcohols in this section and draw their structures