Upper Secondary Chemistry

Experimental Techniques

• Identify and distinguish the common apparatus used for the measurement of time, temperature, mass and volume.
• Analyse information given to suggest, with relevant sketch, appropriate apparatus to be used in experiments.

Separation techniques

• Describe the various methods of separation and purification for the components of mixtures in detail with diagrams.
• Identify the errors made in the given information from the experiment and explain the significance of the errors and how the result will be affected.
• Using information given about the mixture, recognise the type of mixture and suggest the appropriate separation and purification techniques.
• Interpret paper chromatograms by comparing the chromatogram spots with known samples and calculate R_f
• Explain the need to use locating agents in the chromatography of colourless compounds
• Deduce the identities of substances and their purity from given melting point and boiling point data
• Discuss the importance of analysing the purity of substances used in daily life.

Kinetic particle theory

• Explain the motion, arrangement and force of attraction in solid, liquid and gaseous particles with relevant diagrams
• Describe the processes in changing of states in terms of the kinetic particle theory and energy changes.
• Sketch and interpret temperature-time graph and explain in terms of kinetic particle theory
• Apply kinetic particle theory to the context given by analysing the focus of the question and relate it to the motion, arrangement and/or force of attraction in particles.
• Define diffusion in terms of the movement of particles from a region of higher concentration to a region of lower concentration
• Relate the effects of diffusion to real-life examples
• Describe the relationship between the molecular mass, temperature and the rate of diffusion.

Atomic structure

• Compare the similarities and differences between proton, neutron and electron.
• Draw the structure of an atom as containing protons and neutrons in the nucleus and electrons arranged in shells based on its electronic configuration.
• Use the periodic table or given information to calculate atomic number, mass number, electron number and nucleon number and identify the element.
• Able to interpret and use the symbols as shown in the periodic table.
• Define and identify isotopes with proper reasoning given.
• Write the formula of ions by identifying the correct number of electrons lost or gained in order to obtain the electronic configuration of a noble gas.

Fundamentals

• Deduce the formulae of compounds using given information and periodic table.
• Memorise solubility table and use it to identify the correct state symbols for salts.
• Construct balanced chemical and ionic equations with state symbols.

Elements, compounds and mixtures

• Define elements, compounds and mixtures and state their differences in terms of their melting and boiling point, proportion, separation technique and formation.
• Able to differentiate elements, compounds and mixtures based on diagrams given.
• Classify substances given into elements, compounds and mixtures by analysing their physical properties.

Chemical bonding

• Explain and compare the formation of ionic, covalent and metallic bonds.
• Master the structure of ionic compounds, covalent compounds and metals with the aid of relevant diagrams.
• Draw ‘dot-and-cross’ diagrams for ionic and covalent compounds with proper labelling.
• Describe, with reasoning, the physical properties of ionic compounds, covalent compounds and metals.
• Differentiate the structure and properties of simple molecular substances from giant molecular substances.
• Compare the bonding and structures of diamond and graphite which leads to the differences in their properties and uses.
• Analyse given data and diagrams to suggest the type of bonding by considering the nature of the elements and its physical and chemical properties.
• Deduce the structure and bonding of other unfamiliar substances by linking the information given to known substances.

Mole concept

• Define and calculate relative atomic mass and relative molecular mass.
• Calculate, with the aid of a table, empirical and molecular formulae.
• Master all six formulae needed to calculate number of moles of a substance using given information by examining the state of substances and the units of values given.
• Identify the limiting reactants whenever necessary before comparing mole ratio.
• Uses mole ratio accurately to calculate the number of moles of other substances used up or produced in the same reaction
• Calculate and recognise the differences between percentage yield, percentage purity and percentage mass of an element in a compound.

Qualitative analysis

• Describe the use of aqueous sodium hydroxide and aqueous ammonia to identify various cations.
• Distinguish the tests used to identify the various anions and gases.
• Interpret data given by summarising it in a flowchart and linking the tests with the given information.
• Write chemical equation for the relevant reaction in the experiment.

Electrolysis

• Explain electrolysis as the conduction of electricity by an ionic compound, in molten or aqueous form, causing the decomposition of the electrolyte.
• Use electrolysis to prove that the giant lattice structure in ionic compound is broken when in molten and aqueous state inducing the presence of mobile ions.
• Predict, with proper reasoning, the products of the electrolysis of molten binary compound and aqueous electrolyte by considering the selective discharge for ions, concentration of electrolyte and nature of electrodes.
• Construct ionic equations for the reactions occurring at each electrode during the electrolysis.
• Describe the electrolysis of aqueous copper(II) sulfate with copper electrodes to purify copper and relate it to purification of other metals that uses similar concept.
• Describe, with the aid of diagram, the electroplating of metals and its uses
• Explain the use of simple cells to produce electricity using the concept of reactivity series of metals and redox reactions.

Energy changes

• Define exothermic and endothermic reactions in terms of their enthalpy change and bond forming/breaking.
• Analyse given information to identify the energy change of a reaction.
• Sketch energy profile and energy level diagrams annotating clearly the enthalpy changes and activation energies.
• Calculate overall enthalpy change of a reaction by drawing the structural formulae of all the reactants and products involved in the reaction to identify the bonds broken and formed.
• Describe hydrogen, as a potential fuel, reacting with oxygen to generate electricity directly in a fuel cell.

Speed of reaction

• Describe, using collision theory, the effect of concentration, pressure, particle size, catalyst and temperature on the speed of reactions.
• Define the term catalyst, its properties and its uses in industrial processes and our body.
• Draw energy level against progress of reaction graph to explain how lowered activation energies in catalysed reactions account for the increase in speed of reactions.
• Interpret the speed of reaction graph by explaining three main parts of the graph: initial, intermediate and final speed.
• Design an experiment to investigate the effect of a given variable on the speed of a reaction with a proposed outcome.
• Sketch and explain the graphs that will be obtained from the experiment above based on its speed of reaction and the number of moles of product formed.

Redox

• Define oxidation and reduction in terms of gaining/losing oxygen and hydrogen, electron transfer and changes in oxidation state
• From given information, explain redox reactions using the appropriate definition.
• Test for oxidising and reducing agents using aqueous potassium iodide and acidified potassium manganate(VII) by observing colour changes.

Acids and bases

• Define acid and alkali as substances that dissolve in water to release hydrogen ions and hydroxide ions respectively.
• Compare the similarities and differences between bases and alkali in terms of its definition and properties.
• Describe the physical and chemical properties of acids and bases.
• Test for acids and alkalis using physical and chemical tests according to the question.
• Appreciate the importance of pH scale and common indicators to determine acidity and alkalinity of substances.
• Discuss the difference between strong and weak acids/alkalis based on the extent of ionisation.
• State the uses of sulfuric acid in real-life examples
• Recognise and explain neutralisation reaction and its importance in controlling pH of substances.
• Classify four types of oxides in terms of the elements it contained, reactions and examples.

Salts

• Use a flowchart and solubility table for common salts to identify the appropriate techniques to be used in the preparation, separation and purification of salts.
• List suitable starting materials to obtain the salt required based on its nature and state.
• Explain in detail, with the aid of diagrams, the three techniques used (precipitation, titration and adding excess) to prepare salts.

Ammonia

• List the essential conditions for the manufacture of ammonia by the Haber process and appreciate the importance of it.
• State the source of reactants nitrogen and hydrogen used in Haber process.
• Recognise that Haber process is a reversible reaction and explain how this affect the yield of ammonia obtained.
• Describe the importance of ammonia in forming fertilisers and compare the effectiveness of various fertilisers.

Periodicity

• Observe that the elements in the Periodic Table are arranged in the order of increasing proton number
• Describe the importance of group number and period number to explain the trends in its electronic structure, reactivity and physical properties.
• Predict the properties of elements usingknown trend and given information.
• Describe the physical and chemical properties for Group I, Group VII, Group 0 and transition metals.
• Explain the trends observed down the group of Group I and Group VII
• Analyse given information to identify the position of an unknown substance in the periodic table by considering its properties and trends.
• State the uses of Group 0 and transition elements.

Metals

• Describe the physical properties of metals in terms of their structure and bonding.
• Define alloys as a mixture of a metal with another element.
• Explain, with the aid of diagrams, why alloys have different physical properties to their constituent elements.
• Internalise the reactivity series of common metals and use it to explain their chemical reactions, its tendency to form positive ions, thermal decomposition of its compounds and extraction methods from its ores.
• Deduce the order of reactivity of unknown metals from a given set of experimental results.
• Design an experiment to determine the order of reactivity of unknown metals.
• Appreciate the importance of recycling metals as it is a finite non-renewable resource.
• State the social, economic and environmental issues of recycling metals.
• Outline the five main reactions in the extraction of iron with haematite, limestone and coke as its raw materials in the blast furnace.
• Explain how the percentage composition of iron and carbon in steel will affect its physical properties and uses due to its structure and bonding.
• State the essential conditions for rusting of iron.
• Discuss in detail how the speed of rusting can be increased or decreased.

Air

• State the volume composition of gases present in dry air.
• Name the common atmospheric pollutants, their sources, negative effects to our environment and solutions to reduce the problem.
• Explain the importance of ozone layer and the problems caused due to the depletion of ozone as a result of ozone reacting with chlorofluorocarbons (CFCs).
• Discuss the importance of carbon cycle for living things.
• Recognise that carbon dioxide and methane are greenhouse gases which contribute to global warming when released in large amount.
• Explain the effects of global warming to the environment.

Organic Chemistry

• Recognise petroleum as a mixture of hydrocarbons and describe the use of fractional distillation toseparate it into useful fractions.
• Identify the fractions obtained in the correct order and state their uses.
• Define homologous series as a group of compounds with a general formula, similar chemical properties and showing gradual change in physical properties.
• Describe alkanes, alkenes, alcohol, carboxylic acid and ester as a homologous series with specific general formula.
• Identify their functional group and state their physical properties.
• Draw their structural formula and name the branched and unbranched organic compounds.
• Master their chemical properties by stating their name of reaction, reactants, products, conditions and equations for each reaction.
• Explain their manufacturing processes and appreciate its importance to meet their demand.
• State their common uses and link it to their properties.
• Create a mind map to demonstrate a clear understanding of the relationship between different homologous series and their chemical reactions.
• Define isomerism and analyse structural formulae of organic compounds to identify and draw possible isomers.
• Compare saturated and unsaturated hydrocarbons in terms of their definition, structure, reactions and uses.
• Outline the test used to differentiate saturated from unsaturated compound.
• Relate carboxylic acids to the physical and chemical properties of weak acids.
• Describe macromolecules as large molecules made up of many small units.
• Observe different monomers and linkages that make up various macromolecules by comparing their structural formulae.
• Discuss the formation of polymers by addition and condensation polymerisation by identifying its monomer, reactants, products and condition.
• Comprehend the differences between the structure of monomer, polymer and repeating unit using given information and draw their structure.
• State the uses of common polymers such as poly(ethene), nylon and Terylene.
• Describe the pollution problems caused by the disposal of non-biodegradable plastics.

MCQ questions

• To be drilled on common MCQ questions to have a better time management during exam.
• To eliminate wrong answers and choose the best answer from the given choices.

Short-answer questions

• Apply the appropriate concept and formulae in standard questions.
• Ensure all the keypoints are explained clearly to obtain maximum marks.

Application questions

• To analyse the question by focusing on important information given and relating it to the concepts taught
• Use proper scientific terms and answering techniques to explain the concepts.