Science 0653 — specification explorer

1. The particulate nature of matter

• C1.1.1State the distinguishing properties of solids, liquids and gases
• C1.1.2Describe the structure of solids, liquids and gases in terms of particle separation, arrangement and types of motion
• C1.1.3Describe the changes of state in terms of melting, boiling, evaporation, freezing and condensation temperature of a gas in terms of the motion of its particles molecule and ion
• C1.1.4Explain changes of state in terms of particle theory and the energy changes involved

1. Measurement

• C2.1.1Name and suggest appropriate apparatus for the measurement of time, temperature, mass and volume, including burettes, pipettes and measuring cylinders

2. Criteria of purity

• C2.2.1Interpret simple chromatograms
• C2.2.2Interpret simple chromatograms, including the use of R values

3. Methods of purification

• C2.3.1Describe and explain methods of separation and purification by the use of a suitable solvent, filtration, crystallisation, distillation, fractional distillation and paper chromatography
• C2.3.2Suggest suitable separation and purification techniques, given information about the substances involved

1. Physical and chemical changes

• C3.1.1Identify physical and chemical changes, and understand the differences between them

2. Elements, compounds and mixtures

• C3.2.1Describe the differences between elements, mixtures and compounds, and between metals and non-metals
• C3.2.2Define the terms solvent , solute , solution and concentration

3. Atomic structure and the Periodic Table

• C3.3.1Describe the structure of an atom in terms of a central nucleus, containing protons and neutrons, and ‘shells’ of electrons
• C3.3.2Describe the build-up of electrons in ‘shells’ and understand the significance of the noble gas electronic structures and of the outer shell electrons (The ideas of the distribution of electrons in s and p orbitals and in d-block elements are not required)
• C3.3.3State the charges and approximate relative masses of protons, neutrons and electrons
• C3.3.4Define and use proton number (atomic number) as the number of protons in the nucleus of an atom
• C3.3.5Define and use nucleon numbe r (mass number) as the total number of protons and neutrons in the nucleus of an atom Note: a copy of the Periodic Table, as shown in the Appendix, will be provided in Papers 1, 2, 3 and 4.
• C3.3.6Use proton number and the simple structure of atoms to explain the basis of the Periodic Table, with special reference to the elements of proton numbers 1 to 20

4. Ions and ionic bonds

• C3.4.1Describe the formation of ions by electron loss or gain
• C3.4.2Use dot-and-cross diagrams to describe the formation of ionic bonds between Group I and Group VII
• C3.4.3Describe the formation of ionic bonds between metallic and non-metallic elements to include the strong attraction between ions because of their opposite electrical charges
• C3.4.4Describe the lattice structure of ionic compounds as a regular arrangement of alternating positive and negative ions, exemplified by the sodium chloride structure

5. Molecules and covalent bonds

• C3.5.1State that non-metallic elements form simple molecules with covalent bonds between atoms
• C3.5.2Describe the formation of single covalent bonds in H , C l , H O, CH , NH and HC l as the sharing of pairs of electrons leading to the noble gas configuration including the use of dot-and-cross diagrams and electrical conductivity between ionic and covalent compounds
• C3.5.3Use and draw dot-and-cross diagrams to represent the bonding in the more complex covalent molecules such as N , C H , CH OH, and CO boiling point of ionic and covalent compounds in terms of attractive forces

1. Stoichiometry

• C4.1.1Use the symbols of the elements and write the formulae of simple compounds the relative numbers of atoms present a model or a diagrammatic representation
• C4.1.2Determine the formula of an ionic compound from the charges on the ions present symbols, including ionic equations

1. Electricity and chemistry

• C5.1.1Define electrolysis as the breakdown of an ionic compound when molten or in aqueous solution by the passage of electricity
• C5.1.2

  Use the terms inert electrode , electrolyte , anode and cathode observations made, using inert electrodes (platinum or carbon), in the electrolysis of:

  • molten lead( II ) bromide
  • concentrated aqueous sodium chloride
  • dilute sulfuric acid
• C5.1.3Describe electrolysis in terms of the ions present and the reactions at the electrodes, in terms of gain of electrons by cations and loss of electrons by anions to form atoms specified molten binary compound

1. Energy changes in chemical reactions

• C6.1.1Describe the meaning of exothermic and endothermic reactions
• C6.1.2Describe bond breaking as an endothermic process and bond forming as an exothermic process
• C6.1.3Draw and label energy level diagrams for exothermic and endothermic reactions using data provided
• C6.1.4Interpret energy level diagrams showing exothermic and endothermic reactions and the activation energy of a reaction

1. Rate (speed) of reaction

• C7.1.1Describe practical methods for investigating the rate of a reaction which produces a gas
• C7.1.2Interpret data obtained from experiments concerned with rate of reaction size, catalysts and temperature on the rate of reactions Note: Candidates should be encouraged to use the term rate rather than speed .
• C7.1.3Suggest suitable apparatus, given information, for experiments, including collection of gases and measurement of rates of reaction concentration in terms of frequency of collisions between reacting particles temperature in terms of the frequency of collisions between reacting particles and more colliding particles possessing the minimum energy (activation energy) to react

2. Redox

• C7.2.1Describe oxidation and reduction in chemical reactions in terms of oxygen loss/gain (Oxidation state limited to its use to name ions, e.g. iron( II ), iron( III ), copper( II ).)
• C7.2.2Define and identify an oxidising agent as a substance which oxidises another substance during a redox reaction and a reducing agent as a substance which reduces another substance during a redox reaction

1. The characteristic properties of acids and bases

• C8.1.1Describe neutrality and relative acidity and alkalinity in terms of pH (whole numbers only) measured using universal indicator
• C8.1.2Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates
• C8.1.3Describe and explain the importance of controlling acidity in soil

2. Preparation of salts

• C8.2.1Describe the preparation, separation and purification of salts using techniques specified in Section C2 and the reactions specified in Section
• C8.2.2Suggest a method of making a given salt from suitable starting material, given appropriate information

3. Identification of ions and gases

• C8.3.1Describe and use the following tests to identify: aqueous cations: ammonium, calcium, copper( II ), iron( II ), iron( III ) and zinc, by means of aqueous sodium hydroxide and aqueous ammonia as appropriate (formulae of complex ions are not required). cations : flame tests to identify lithium, sodium, potassium and copper( II ) anions : carbonate (by reaction with dilute acid and then limewater), chloride (by reaction under acidic conditions with aqueous silver nitrate), nitrate (by reduction with aluminium) and sulfate (by reaction under acidic conditions with aqueous barium ions) gases : ammonia (using damp red litmus paper), carbon dioxide (using limewater), chlorine (using damp litmus paper), hydrogen (using a lighted splint), oxygen (using a glowing splint)

1. The Periodic Table

• C9.1.1Describe the Periodic Table as a method of classifying elements and its use to predict properties of elements

2. Periodic trends

• C9.2.1Describe the change from metallic to non-metallic character across a period
• C9.2.2Describe and explain the relationship between group number, number of outer-shell electrons and metallic/non-metallic character

3. Group properties

• C9.3.1Describe lithium, sodium and potassium in Group I as a collection of relatively soft metals showing a trend in melting point, density and reaction with water iodine in Group VII, as a collection of diatomic non-metals showing a trend in colour and physical state
• C9.3.2Predict the properties of other elements in Group I, given data, where appropriate iodine with other halide ions Group VII, given data where appropriate the elements concerned

4. Transition elements

• C9.4.1Describe the transition elements as a collection of metals having high densities, high melting points and forming coloured compounds, and which, as elements and compounds, often act as catalysts

5. Noble gases

• C9.5.1Describe the noble gases, in Group VIII or 0, as being unreactive, monoatomic gases and explain this in terms of electronic structure
• C9.5.2State the uses of the noble gases in providing an inert atmosphere, i.e. argon in lamps, helium for filling balloons

1. Properties of metals

• C10.1.1Describe the general physical properties of metals as solids with high melting and boiling points, malleable and good conductors of heat and electricity
• C10.1.2Describe alloys, such as brass, as mixtures of a metal with other elements
• C10.1.3Explain in terms of their properties why alloys are used instead of pure metals
• C10.1.4Identify representations of alloys from diagrams of structure

2. Reactivity series

• C10.2.1

  Place in order of reactivity: potassium, sodium, calcium, magnesium, aluminium, (carbon), zinc, iron, (hydrogen) and copper, by reference to the reactions, if any, of the elements with: experimental results:

  • water or steam
  • dilute hydrochloric acid
  • reduction of their oxides with carbon
• C10.2.2Describe the reactivity series in terms of the tendency of a metal to form its positive ion, illustrated by its reaction, if any, with the aqueous ions of other listed metals

3. Extraction of metals from their ores

• C10.3.1Describe the use of carbon in the extraction of copper from copper oxide bauxite by electrolysis hence the need to recycle metals
• C10.3.2Describe and explain the essential reactions in the extraction of iron from hematite in the blast furnace C + O → CO C + CO → 2CO Fe O + 3CO → 2Fe + 3CO its ore to its position in the reactivity series for the metals listed in Section C10.2 and for other metals, given information

1. Water

• C11.1.1Describe a chemical test for water using copper( II ) sulfate and cobalt( II ) chloride
• C11.1.2Describe, in outline, the treatment of the water supply in terms of filtration and chlorination

2. Air

• C11.2.1State the composition of clean air as being a mixture of 78% nitrogen, 21% oxygen and small quantities of noble gases, water vapour and carbon dioxide
• C11.2.2Name the common pollutants in air as being carbon monoxide, sulfur dioxide and oxides of nitrogen
• C11.2.3State the adverse effect of these common air pollutants on buildings and on health
• C11.2.4State the conditions required for the rusting of iron (presence of oxygen and water)
• C11.2.5Describe and explain barrier methods of rust prevention, including paint and other coatings

3. Carbon dioxide and methane

• C11.3.1

  State the formation of carbon dioxide: carbon-containing substances and a carbonate calcium carbonate:

  • as a product of complete combustion of
  • as a product of respiration
  • as a product of the reaction between an acid
  • as a product of thermal decomposition of
• C11.3.2State that carbon dioxide and methane are greenhouse gases
• C11.3.3State that increased concentrations of greenhouse gases cause an enhanced greenhouse effect, which may contribute to climate change

1. Fuels

• C12.1.1State that coal, natural gas and petroleum are fossil fuels that produce carbon dioxide on combustion
• C12.1.2Name methane as the main constituent of natural gas
• C12.1.3

  Describe petroleum as a mixture of hydrocarbons and its separation into useful fractions by fractional distillation cooking chemicals:

  • refinery gas for bottled gas for heating and
  • gasoline fraction for fuel (petrol) in cars
  • naphtha fraction as a feedstock for making
  • diesel oil / gas oil for fuel in diesel engines
  • bitumen for road surfaces
• C12.1.4Describe the properties of molecules within a fraction

2. Homologous series

• C12.2.1Describe the homologous series of alkanes and alkenes as families of compounds with the same general formula and similar chemical properties

3. Alkanes

• C12.3.1Describe alkanes as saturated hydrocarbons whose molecules contain only single covalent bonds
• C12.3.2Describe the properties of alkanes (exemplified by methane) as being generally unreactive, except in terms of burning
• C12.3.3Describe the complete combustion of hydrocarbons to give carbon dioxide and water

4. Alkenes

• C12.4.1Describe alkenes as unsaturated hydrocarbons whose molecules contain one double covalent bond
• C12.4.2

  State that cracking is a reaction that produces alkenes hydrocarbons: example of addition polymerisation of monomer units:

  • from molecular structures
  • by their reaction with aqueous bromine
• C12.4.3Describe the formation of smaller alkanes, alkenes and hydrogen by the cracking of larger alkane molecules and state the conditions required for cracking