reacting acids and bases and insoluble salts by precipitation reactions hydrogen atoms with light with the expected observations generated by each model of the atom. THINKING CONCEPTUALLY EL(u) the basic nature of the oxides and hydroxides of Group 2 (Mg–Ba) Rutherford experiment simulation (Michael W. Davidson and The Florida State University) This website simulates the Rutherford ‘gold foil’ experiment and is accompanied by a clear explanation of how the experiment challenged the existing atomic model. THINKING CONCEPTUALLY EL(v) the electromagnetic spectrum in order of increasing frequency and energy and decreasing wavelength: infrared, visible, ultraviolet Gridlocks game: Mass number and atomic number (Royal Society of Chemistry) This game is designed around the principle of Sudoku puzzles. THINKING CONCEPTUALLY EL(w) transitions between electronic energy levels in (i) the occurrence of absorption and emission atomic spectra in of transition of electrons between electronic energy levels Gridlocks game: Subatomic particles (Royal Society of Chemistry) This game is designed around the principle of Sudoku puzzles. THINKING CONCEPTUALLY
Properties of hydrogen chloride (Practical Chemistry) This is a particularly good experiment for demonstrating the solubility of hydrogen chloride, but the fountain demonstration should be practiced first and always carried out in a fume cupboard. THINKING CONCEPTUALLY Astronomy: Spectroscopy (YouTube) This series of three YouTube videos puts atomic line spectra in the context of astronomy. The first two videos are the most relevant with the first going over basic ideas involving electronic energy levels, and the second taking those ideas forward explaining how they provide information on stars. THINKING CONTEXTUALLY Light energy and photochemical reactions (Steve Spangler Science) This simple practical (follow the ‘Now Try This!’ section) uses photosensitive paper to show the link between the wavelength or frequency of light and the energy it carries. THINKING CONCEPTUALLY
ES(k) the reactions between halide ions (Cl–, Br– and I–) and silver ions (Ag+) and ionic equations to represent these precipitation reactions, the colours of the precipitates and the solubility of silver halides in ammonia Alchemy: Copper refining (Royal Society of Chemistry) The electronics industry requires copper to be of an extremely high purity and this set of resources includes worksheets and clips of the electrolysis of copper to produce high purity metal. THINKING CONTEXTUALLY ES(l) the preparation of HCl; the preparation of HBr and HI by using the halide and phosphoric acid; the action of sulfuric acid on chlorides, bromides and iodides Electrolysis of copper (II) sulfate solution (Nuffield Foundation) Using electrolysis as a tool to plate materials has many applications in industry and the manufacture of jewellery. This practical work allows learners to explore electroplating and how it could be used in real-world situations. THINKING CONTEXTUALLY ES(m) the properties of the hydrogen halides: different thermal stabilities, similar reaction with ammonia and acidity, different reactions with sulfuric acid Anodising aluminium (Nuffield Foundation) The anodising of aluminium is a technique used in industry to thicken the protective layer of aluminium oxide that protects the metal underneath. Here the learners complete this procedure in the lab. THINKING CONTEXTUALLY
Reaction of hydrogen and chlorine of the reaction between hydrogen and chlorine. THINKING CONCEPTUALLY Microscale reactions of chlorine (Practical Chemistry) Chlorine is generated on a scale in a petri dish, and is used to investigate its properties including reaction with water and displacement reactions with halide salts. THINKING CONCEPTUALLY Formation of silver halide precipitates A video showing the colours of the different silver halide precipitates (not the solubility). THINKING CONCEPTUALLY Gridlocks game: Reactions of sodium halides with concentrated sulfuric acid This game is designed around the principle of Sudoku puzzles. THINKING CONCEPTUALLY
in percentage concentration and in parts per million (ppm) help learners think of mixing and related phenomena (e.g. dissolving) in terms of breaking and making intermolecular bonds. THINKING CONTEXTUALLY OZ(j) the recognition of and formulae for examples of members of the following homologous series: (i) haloalkanes, including systematic nomenclature (ii) amines Assessment for learning chemistry: What are hydrogen and where are they found? (Royal Society of Chemistry) A series of activities that introduce hydrogen bonds as a specific type of intermolecular bond. This resource begins with the example of water, but also points out that hydrogen bonds are found in other substances. Classroom discussion and peer assessment are encouraged. THINKING CONCEPTUALLY OZ(k) the characteristic properties of haloalkanes, comparing fluoro-, bromo- and iodo-compounds, considering the following aspects: (i) boiling points (depend on intermolecular bonds) (ii) nucleophilic substitution with water and hydroxide ions to form alcohols, and with ammonia to form amines Demo of water expanding when it freezes (Royal Society of Chemistry) This simple teacher demonstration of a plastic bottle of water splitting when it is frozen can be used to initiate discussions about the properties of water in various states. Alternatively, a video could be shown in class to show how water expands when it freezes. THINKING CONTEXTUALLY
WM(d) the following reactions of alcohols and two-step syntheses involving reactions and other organic reactions in the specification: (i) with carboxylic acids, in the presence of concentrated sulfuric acid or concentrated hydrochloric acid (or with acid anhydrides) to form esters (ii) oxidation to carbonyl compounds (aldehydes and ketones) and carboxylic acids with acidified dichromate(VI) solution, including the importance of the condition (reflux or distillation) under which it is done (iii) dehydration to form alkenes using heated Al2O3 or refluxing with concentrated H2SO4 (iv) substitution reactions to make haloalkanes Making esters from acids and alcohols (Nuffield Foundation) Details of a class experiment to make a range of esters. CLEAPSS offer a reduced scale version of this experiment. THINKING CONCEPTUALLY WM(e) techniques and procedures for making a solid organic product and for purifying it using filtration under reduced pressure and re-crystallisation (including choice of solvent and how impurities are removed); techniques and procedures for melting determination and thin layer chromatography Thin layer chromatography (The University of Alberta) This is a useful information page on TLC with video and FAQs. THINKING CONCEPTUALLY
PL(n) the reactions of acyl chlorides with amines and alcohols Carbon-13 NMR: Topic exploration pack This OCR resource contains activities that can be used to introduce the key ideas of carbon-13 NMR. THINKING CONCEPTUALLY PL(o) the differences between addition and condensation polymerisation NMR learning activities (Royal Society of Chemistry) The RSC have published some simple learning activities to encourage thinking about chemical shift and multiplicity. THINKING CONCEPTUALLY PL(p) the relationship between the structural formula of a condensation polymer and the structural formulae of its monomer(s) and vice versa How MRI works (Howstuffworks) Learners interested in medicine and medical physics may well wish to explore the uses of magnetic resonance in body imaging. This is significantly removed from the use of NMR for identifying organic compounds. THINKING CONTEXTUALLY PL(q) optical isomerism: (i) diagrams to represent optical stereoisomers of molecules (ii) the use of the term chiral as applied to a molecule and identifying carbon Spectroscopy tutorial: Example problem directory (The University of Colorado) A useful summary of functional groups and how they can be detected using different analytical techniques.
(iii) techniques and procedures for measuring the energy transferred in experiments involving enthalpy changes in solution O(c) the dependence of the lattice enthalpy of an ionic compound and the enthalpy change of hydration of ions on the charge density of the ions An introduction to entropy (BBC) In this 5-minute video, Professor Brian Cox explains entropy in a qualitative way by looking at how sand behaves in an abandoned mining town in the Namib desert. This is a very visual way to introduce the concept at the beginning of a study of entropy. THINKING CONCEPTUALLY O(d) qualitative entropy changes (of the system); entropy as a measure of the number of ways that molecules and their associated energy quanta can be arranged Quantum casino (Royal Society of Chemistry) The site has an extensive, indexed list of tutorials explain entropy like a text book with embedded videos), simulations (to show entropy in terms of ‘number of ways’ that particles can be arranged and videos of reactions). The full site explores Gibbs free energy, which is not needed for this specification, but this is in a separate section that can be left out. THINKING CONCEPTUALLY
knowledge and understanding develop over time (HSW7). THINKING CONTEXTUALLY O(k) the term weak acid and equations for its ionisation in water; acidity constant (‘dissociation constant’) Ka, pKa; techniques and procedures to measure the pH of a solution pH calculations worksheet (OCR Lesson Element) A worksheet going through pH calculations in ever increasing depth. THINKING CONCEPTUALLY O(l) the term pH, and pH calculations involving: (i) strong acids (ii) strong bases, using Kw (iii) weak (including calculating any of the terms pH, Ka and concentration from any two others, being aware of the approximations made) pH and buffers in action (OCR Lesson Element) This worksheet real illustrations of pH and buffers in food, biological and environmental science. This resource can be used to develop chemical literacy skills. THINKING CONTEXTUALLY O(m) buffer solutions based on solutions of weak acids and their salts: (i) the meaning of the term buffer (ii) how buffers work (including in everyday applications) (iii) buffer solution calculations Greenhouse effect (Royal Society of Chemistry) This demonstration from the Royal Society of Chemistry is designed to show how visible and UV light can be as IR and cause a warming effect. THINKING CONCEPTUALLY
O(n) the ‘greenhouse effect’, in terms of: (i) solar energy reaching Earth mainly as visible and UV (ii) absorbing some of this energy, heating up and radiating IR (iii) greenhouse gases (e.g. carbon dioxide and methane) in the troposphere absorbing some of this IR, in the ‘IR window’ (iv) absorption of IR by greenhouse gas molecules increases the vibrational energy of their bonds, the energy is transferred to other molecules by collisions, thus increasing their kinetic energy and raising the temperature (v) greenhouse gas molecules also some of the absorbed IR in all directions, some of which heats up the Earth (vi) increased concentrations of greenhouse gases leading to an enhanced greenhouse effect. Greenhouse gas simulation (PhET, University of Colorado) This simulation demonstrates how the absorption and re-emission of infra-red photons from the earth’s surface affects the temperature of the atmosphere. Learners can directly alter the composition of the atmosphere, determine the effect of clouds and also investigate the composition of the air during the last ice age, before the industrial revolution and in the present day. THINKING CONTEXTUALLY
DM(e) the action of an electrochemical cell in of half-equations and external electron flow and the ion flow in the salt bridge Displacement reactions between metals and their salts (Nuffield Foundation) The familiar concept of displacement reactions and the prediction of the result of such a reaction using the reactivity series lay the foundation for a deep understanding of the electrochemical series and the nature of electrode potentials. This short practical reviews these concepts ready to develop the learners’ ideas. THINKING CONCEPTUALLY DM(f) the term standard electrode potential and its measurement a hydrogen electrode; use of standard electrode potentials to: (i) calculate (ii) predict the feasibility of reactions, and the reasons why a reaction may not occur (iii) explain rusting, and its prevention, in terms of electrochemical processes The ammonium dichromate(VI) volcano (Nuffield Foundation) This is a great teacher demonstration that shows how strongly oxidising Cr2O72– ions produce nitrogen and water from the ammonium ions. The brightly coloured orange chromate(VI) ions are reduced to produce a mass of green chromium(III) oxide, which can be saved and used in the oxidation of ammonia demonstration later. THINKING CONCEPTUALLY DM(g) transition metals as d-block elements forming one or more stable ions which have incompletely filled Reduction of vanadium compounds by zinc (Royal Society of Chemistry) A very colourful activity that works well as a plenary to the section on colour as well
THINKING CONTEXTUALLY CD(d) the formulae of arenes and their derivatives (aromatic compounds): (i) the delocalisation of electrons in compounds (ii) how delocalisation accounts for characteristic properties Microscale Chemistry: The microscale synthesis of azo dyes (Royal Society of Chemistry) In this experiment an azo dye is synthesized and used to dye a piece of cotton. Different azo dyes can be synthesized by altering the diazonium salt and the coupling agent. The subtly different colours produced can be linked to changes in delocalization across the dye molecule and the corresponding changes in the energy gap between lower and excited electronic energy levels. THINKING CONTEXTUALLY CD(e) the two common representations of the benzene molecule and relation to: (i) the shape of the molecule (ii) bonding in the molecule (including a treatment of enthalpy change of hydrogenation) The solar spark: Make a Gratzel cell (Royal Society of Chemistry) A Gratzel cell is a simple form of solar cell that can be produced using materials available via The Solar Spark. This practical allows learners to produce their own solar cell made with raspberries! The chemistry behind this activity combines ideas about redox and dyes. It would be suitable as an activity done towards the end of the course. THINKING CONTEXTUALLY
CD(i) the following reactions involving carbonyl compounds (aldehydes and ketones): (i) oxidation of aldehydes to carboxylic acids using acidified dichromate, under reflux (ii) reaction with Fehling’s solution and Tollens' reagent (iii) reaction with cyanide ions to form the cyanohydrin Gridlocks: Functional groups (Royal Society of Chemistry) An electronic game in which learners match together the names and structures of organic functional groups. One of several similar games that cover different aspects of organic chemistry. THINKING CONCEPTUALLY CD(j) use of organic reactions and reaction conditions mentioned here and elsewhere in the specification to suggest and explain synthetic routes for preparing organic compounds Major organic compounds in herbs and spices (Royal Society of Chemistry) An infographic which identifies the major organic compounds that contribute to the flavour, aroma or colour of common herbs and spices. Posters like this can be used for ‘functional group spotting’, and potentially for thinking about synthesis routes (though not all compounds depicted here will be suitable for that purpose). THINKING CONTEXTUALLY CD(k) the mechanism of the nucleophilic addition reaction between a carbonyl compound and CN–, using ‘curly arrows’ and partial charges Starters for 10: Compounds with amine groups (Royal Society of Chemistry) Sets of questions on amines, amides and amino acids. Some of them are quite challenging.
THINKING CONCEPTUALLY CD(l) organic mechanisms: (i) use of the following terms to classify organic reactions: addition, condensation, elimination, substitution, oxidation, reduction, hydrolysis (ii) use of ‘curly arrows’ and partial charges, where appropriate, to describe unfamiliar mechanisms, given appropriate information The formation of by the reaction between hydroxybenzene and chlorine gas (Royal Society of Chemistry) A class experiment or demonstration that can be used to introduce electrophilic substitution reactions. THINKING CONCEPTUALLY CD(m) the origins of colour (and UV absorption) in organic molecules Aromatic reactions map infographic (Royal Society of Chemistry) A summary of the reactions of aromatic compounds that can be used as a poster or learner handout. One of a number of infographic sheets that organic chemistry. THINKING CONCEPTUALLY CD(n) the general principles of chromatography: (i) sample injected into carrier gas stream (ii) column consisting of high boiling liquid on porous support (iii) detection of the emerging compounds (sometimes involving mass spectrometry) Chromatography (Explainthatstuff) An article at the right level that explains the general principles of chromatography, and discusses the various forms. THINKING CONCEPTUALLY