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1. Chemistry 11–12 · Year 11

   A circus of reaction types: synthesis, decomposition, combustion, precipitation, acid-base and acid-carbonate

   Chemical change shows itself as a new substance with new properties (a gas, a precipitate, a colour change, a temperature change or light), and each reaction type has a predictable product pattern.

   PracticalMedium risk

2. Chemistry 11–12 · Year 11

   A spontaneous endothermic reaction: barium hydroxide octahydrate with ammonium chloride (teacher demonstration)

   A reaction can run on its own while absorbing heat because the large increase in entropy (solids to a slush of ions, water and ammonia gas) outweighs the enthalpy cost.

   Teacher-led practicalPracticalHigh risk

3. Chemistry 11–12 · Year 11

   Building a metal activity series from reactions with water, dilute acid, oxygen and metal-ion solutions

   Metals can be ranked by how readily they give up electrons; a more active metal displaces a less active metal from solution and reacts faster with acid.

   PracticalMedium risk

4. Chemistry 11–12 · Year 11

   Burning magnesium in a crucible: mass gain and the empirical formula of magnesium oxide

   Elements combine in a fixed whole-number mole ratio; the mass of oxygen gained by a weighed strip of magnesium gives that ratio directly.

   Practical, model not builtMedium risk

5. Chemistry 11–12 · Year 11

   Calorimetry of ethanol combustion: measuring the enthalpy of combustion and explaining the shortfall

   The heat released by burning a weighed mass of fuel is captured by a known mass of water; the enthalpy of combustion per mole follows, and the gap from the accepted value measures heat loss.

   Practical, model not builtMedium risk

6. Chemistry 11–12 · Year 11

   Catalysts for the decomposition of hydrogen peroxide: manganese(IV) oxide, potassium iodide and catalase

   A catalyst speeds a reaction by providing a pathway with a lower activation energy and is left unchanged; different catalysts lower the barrier by different amounts.

   Practical, model not builtMedium risk

7. Chemistry 11–12 · Year 11

   Comparing the specific heat capacities of aluminium and copper by the method of mixtures

   Equal masses of different substances heated through the same temperature change store different amounts of energy, and the specific heat capacity in q = m c delta T measures that difference.

   Practical, model not builtLow risk

8. Chemistry 11–12 · Year 11

   Conservation of mass: vinegar and sodium hydrogen carbonate in an open cup and a capped bottle, and a precipitation on the balance

   Mass is conserved in every chemical reaction; an apparent loss in an open system is the mass of gas that left, which the balanced equation predicts.

   Practical, model not builtLow risk

9. Chemistry 11–12 · Year 11

   Galvanic cells with a salt bridge: measuring and predicting cell potentials

   A spontaneous redox reaction split into two half-cells drives electrons through a wire; the measured voltage is the difference between the two half-cells' reduction potentials.

   Practical, model not builtMedium risk

10. Chemistry 11–12 · Year 11

    Hess's law: the enthalpy of hydration of copper(II) sulfate from two dissolution measurements

    An enthalpy change that cannot be measured directly is found by combining changes along another route, because enthalpy change depends only on the start and end states.

    Practical, model not builtMedium risk

11. Chemistry 11–12 · Year 11

    Magnesium in hydrochloric acid: gas volume against time, surface area and concentration

    The gradient of a volume-time graph is the reaction rate; it is steepest at the start, falls as reactant is used up, and rises with surface area and acid concentration.

    Practical, model not builtMedium risk

12. Chemistry 11–12 · Year 11

    Reactivity of Group 1 and Group 2 metals with water down and across the periodic table

    Reactivity with water rises down Group 1 (lithium to sodium) and is lower for the Group 2 metals, following the trend in first ionisation energy.

    Teacher-led practicalPracticalHigh risk

13. Chemistry 11–12 · Year 11

    Sodium thiosulfate and hydrochloric acid (the disappearing cross): rate against temperature and concentration

    Reaction rate rises with concentration because collisions are more frequent, and with temperature because a larger fraction of collisions carry the activation energy.

    Practical, model not builtMedium risk

14. Chemistry 11–12 · Year 11

    Temperature changes on dissolving ionic solids and on burning a fuel: classifying reactions as endothermic or exothermic

    Energy released or absorbed by bond changes shows up as a temperature change of the surroundings, measured in an insulated cup and predicted from enthalpy data.

    Practical, model not builtMedium risk

15. Chemistry 11–12 · Year 11

    The iodine clock: a sharp end point for measuring rate with a data logger

    A reaction whose product is masked until a fixed amount of a second reagent is consumed gives a sudden colour change, so the time to that change measures the average rate exactly.

    PracticalMedium risk

16. Chemistry 11–12 · Year 12

    Measuring the enthalpy of neutralisation of a strong acid with a strong base, and comparing a weak acid

    Neutralisation releases the same heat per mole of water formed for any strong acid with any strong base, because the reaction in every case is hydrogen ion with hydroxide ion.

    Practical, model not builtMedium risk