The GCSE PAG Tracker helps teachers to track learners’ opportunities with the apparatus and techniques, and to ensure that the practical activities chosen fully cover the requirements. The first set of OCR PAG activities are now available on the qualification pages under the Practical Activities section (; ). These activities are: PAG 1.2 Reactivity of metals PAG 2.2 Microscale electrolysis of copper(II) chloride PAG 3.2 Chromatography of leaf chloroplasts PAG 4.1 Extraction of limonene PAG 5.2 The march of the precipitANTs PAG 6.2 The vinegar dilemma PAG 7.1 Prussian blue investigation PAG 8.2 The disappearing cross Note this set of PAG activities does not fully cover all of the required apparatus and techniques. For full coverage, the following practicals are additionally suggested. Practical activity sheets covering these activities are currently in production, and will be available soon. Alternatively, the weblinks below are to suitable Royal Society of Chemistry activities or CLEAPSS activities. A rate of reaction experiment involving gas collection and heating reagents with a water bath – e.g. the effect of temperature on the rate of reaction between hydrochloric acid and magnesium - Synthesis of salt with purification by crystallisation – e.g. synthesis of copper sulfate – Investigating enthalpy changes – e.g. mixing pairs of chemicals and measuring the temperature change - Flame test on metal salts – Titration of a strong acid and alkali - Suggested activities for each Practical Activity group and each type of activity: PAG Traditional/bench Microscale Kitchen-chemistry
1 – Reactivity trends Displacement reactions of the halogens e.g. Practical Chemistry project Reactivity of metals e.g. CLEAPSS ‘Rusting’ nails investigation – iron/zinc/copper in different conditions 2 – Electrolysis Electrolysis of brine, gas test for chlorine and hydrogen. e.g. Royal Society of Chemistry Classic Chemistry Experiment 82 Microscale electrolysis of copper chloride. e.g. CLEAPSS (see also CLEAPSS and – login required) Electrolysis of brine with 9V battery – chlorine gas test. Shot-glass synthesis of CO2 – carbon dioxide gas test. 3 – Separation techniques Preparation of ammonium sulfate e.g. Practical Chemistry project (see also CLEAPSS – login required) Thin layer chromatography e.g. CLEAPSS (see also CLEAPSS and ) Chromatography of food colouring on coffee filters – different separations with water / rubbing alcohol. 4 – Distillation Extracting by steam distillation e.g. Royal Society of Chemistry Chemistry for non-specialists Small-scale steam distillation e.g. CLEAPSS (see also CLEAPSS ) or CLEAPSS (login required) (see also CLEAPSS – login required) Steam distillation of lavender with vegetable steamer 5 – Identification of species Cation/anion/flame tests e.g. Royal Society of Chemistry Classic Chemistry Experiments 80 and Royal Society of Chemistry Chemistry for Microscale precipitation e.g. CLEAPSS – ‘’ (see also CLEAPSS – login required) Distillation of salt water with before and after flame tests 6 – Titration Titration of HCl/H2SO4 with NaOH e.g. Practical Chemistry project (first stage) or (see also CLEAPSS – login required) Microscale titration of carboxylic acids with NaOH e.g. CLEAPSS (see also CLEAPSS - login required) Investigating vinegar and baking soda solutions and mixtures with vegetable/fruit pH indicators.
7 – Production of salts Preparation of (NH4)2SO4 e.g. Classic chemistry experiments #91 ‘’ Production of CuSO4 e.g. CLEAPSS (see also CLEAPSS – login required) Making soap e.g. CLEAPSS (see also CLEAPSS – login required) 8 – Measuring rates of reaction Rate of reaction between Mg & HCl e.g. Practical Chemistry project Reaction energetics e.g. Practical Chemistry project Rate of reaction between acid and thiosulfate e.g. CLEAPSS (see also Royal Society of Chemistry Classic Chemistry Experiment 64 ) Reaction energetics e.g. CLEAPSS (see also CLEAPSS – login required) Rate of reaction between indigestion tables and vinegar – effect of surface area Using home-made overwater collection apparatus (glass olive jar, blutac, straws and an tub and a water bottle).