Author Archives: secondaryscience4all

12. Separation of species by thin-layer chromatography

Separation of species by thin-layer chromatography Analysis of the composition of some common medicines. Method dichloromethane ibuprofen tablet paracetamol tablet caffeine tablet aspirin tablet Anadin Extra tablet (or equivalent containing aspirin, paracetamol and caffeine) pestle and mortar TLC plate capillary tubes developing chamber (or suitable container with lid) access to UV lamp. Preparation of samples Use a pestle and mortar

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11. An investigation of some transition metal compounds

An investigation of some transition metal compounds Most transition metal compounds are coloured. Some of them are used as dyes and pigments. A dye is a soluble coloured compound. A pigment is an insoluble coloured compound. Both dyes and pigments have to be resistant to chemical change. Three solutions, labelled P, Q and R, have been provided by a supplier

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10b. Preparation of a pure organic liquid

The preparation of ethyl ethanoate Requirements ethanol pure (‘glacial’) ethanoic acid concentrated sulfuric acid sodium carbonate solution saturated calcium chloride solution solid anhydrous calcium chloride 250 cm3 round bottomed flask 100 cm3 round bottomed flask reflux condenser 2 x 100 cm3 conical flasks separating funnel anti-bumping granules thermometer (0 – 100 oC). Method  Reaction Add 50 cm3 of ethanol and

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