ASSEMBLING APPARATUS (Programme 1.1; Basic 1.1; Practical 1.1)

Running time: 7:30 mins.
Introduction to "Quickfit" laboratory glassware; greasing joints and using PTFE sleeves; attaching tubing to condensers with fixed and detachable side-arms; supporting glassware with clamps, bosses and stands; setting up apparatus for distillation and refluxing; safety procedures for overnight working.

USING STIRRERS (Programme 1.2; Basic 1.2; Practical 1.2)

Running time: 6:57 mins.
Discussion of the role of stirrers in the laboratory; various types of stirrers: magnetic stirrers, mechanical stirrers; paddle types; attaching a stirrer rod to motor; using sealing of glands for controlled atmospheres e.g. setting up a stirrer with motor, flask and oil cup seal.

HEATING SAMPLES (Programme 1.3; Basic 1.3; Practical 1.3)

Running time: 10:17 mins.
Discussion about the role and choice of heating in the labora tory; using various types of heating: the Bunsen and micro burner, steam baths, stirrer hotplates, oil baths, and heating mantles; safety aspects.

USING A ROTARY EVAPORATOR (Programme 1.4; Basic 1.4; Practical 1.4)

Running time: 4:19 mins.
Introduction to the rotary evaporator; operation of the rotary evaporator: initial set up, mountinng the sample flask, evaporation of solvent from sample, the use of a water bath, obtaining the product; shutdown procedure for safely ending the operation including the disposal of unwanted solvent.

DISTILLATION AT ATMOSPHERIC PRESSURE (Programme 2.1; Basic 2.1; Practical 2.1)

Running time: 7:14 mins.
Introduction to atmospheric pressure distillation; setting up the apparatus for a distillation below 200°C including safe disposal of uncondensed vapours; setting up a water cooled condenser; using a thermometer; heating the sample with oil bath on stirrer hot plate; distillation and collection of distillate; shutdown and dismantling the apparatus.

DISTILLATION AT REDUCED PRESSURE (Programme 2.2; Basic 2.2; Practical 2.2)

Running time: 7:58 mins.
Introduction to reduced pressure distillation; looking at pieces of apparatus: the two-necked Claisen head, the water cooled condenser, the capillary bleed, the use of oxygen-free nitrogen-filled balloon, the multi-flask receiver-adaptor, water pump, solid carbon dioxide/acetone trap, oil bath for heating; carrying out the distillation and collection of fractions. Appendix on making a capillary bleed: drawing soft glass tubing and testing the bleed by passing nitrogen through it while the tip is immersed in acetone.

FRACTIONAL DISTILLATION (Programme 2.3; Basic 2.3; Practical 2.3)

Running time: 5:11 mins.
Introduction to fractional distillation and the design of fractionating columns; demonstration of procedure from initial set up of apparatus to obtaining the fractions, cleaning of the fractionating column and shutting down the equipment.

STEAM DISTILLATION (Programme 2.4; Basic 2.4; Practical 2.4)

Running time: 4:34 mins.
Introduction to steam distillation; demonstration of water- addition steam distillation method using a two-necked flask, splash head, dropping funnel and double-surface condenser; problems arising from low melting point solids; using a steam generator system; shutdown procedure.

SEMI-MICRODISTILLATION (Programme 2.5; Basic 2.5; Practical 2.5)

Running time: 1:49 mins.
Introduction to semi-micro distillation in the laboratory including examination of pear shaped flask for star cracks; demonstration of semi-micro distillation including the use of the micro-burner, and glass wool to aid distillation; distillation under reduced pressure; shutdown procedure.

GRAVITY FILTRATION (Programme 3.1; Basic 3.1; Practical 3.1)

Running time: 5.15 mins.
Introduction to gravity filtration including using fluted paper, funnel selection, and filter paper selection; demonstration of the cold filtration procedure including addition contents to funnel; demonstration of the hot filtration on a steam bath; simple quantitative filtration. Appendix on folding small, medium and large sized fluted filter papers.

SUCTION FILTRATION (Programme 3.2; Basic 3.2; Practical 3.2)

Running time: 7:02 mins.
Introduction to suction filtration; suction filtration using Buchner funnel and flask including the safe use of aspirators and vacuum systems and avoidance of solid precipitating out in flask by pre-cooling; drying the solid; small scale suction filtration using Hirsch funnel and Buchner tube; shutdown procedure.

RECRYSTALLISATION (Programme 3.3; Basic 3.3; Practical 3.3)

Running time: 11:30 mins.
Introduction to recrystallisation; demonstration of recrystallisation including: heating the solvent, adding the compound, hot filtration using a fluted filter paper and short stemmed glass funnel, and obtaining the crystals; washing and drying the crystals. Appendices on: solubility testing, promoting recrystallisation, handling oils and dealing with discoloured samples using activated charcoal.

SUBLIMATION (Programme 3.4; Basic 3.4; Practical 3.4)

Running time: 3:42 mins.
Introduction to sublimation; sublimation as a purification process at atmospheric pressure using camphor; demonstration of reduced pressure technique for less volatile substances e.g. borneol; subliming larger quantities of material.

REFLUXING (Programme 3.5; Basic 3.5; Practical 3.5)

Running time: 3:09 mins.
Introductory discussion on refluxing in the laboratory; demonstration of refluxing including: setting up the apparatus, charging the flask, choosing the heat source, controlling temperature, safety hints; shutdown procedure.

SOLVENT EXTRACTION (Programme 4.1; Basic 4.1; Practical 4.1)

Running time: 8:44 mins.
Introduction to solvent extraction; demonstration of the separating funnel to carry out two extractions: the first with the organic layer lighter than water, the second heavier than water; and drying the extracts. Appendix on handling emulsions, e.g. breaking up an emulsion by adding saturated brine.

SOXHLET EXTRACTION (Programme 4.2; Basic 4.2; Practical 4.2)

Running time: 5:05 mins.
Introductory discussion on the laboratory use of Soxhlet extractor; setting up the Soxhlet extraction apparatus including a demonstration of its unique siphon discharge action, loading the sample, filling the flask and heating the flask; carrying out the extraction; shut down procedure.

CONTINUOUS FLOW EXTRACTION (Programme 4.3; Basic 4.3; Practical 4.3)

Running time: 7:12 mins.
Introduction to continuous flow extraction; choosing the solvent; demonstrations of two types of extraction: the first using a solvent less dense than the sample solvent and the sec ond using a solvent more dense than sample solvent; further post-extraction steps.

DRYING SAMPLES (Programme 4.4; Basic 4.4; Practical 4.4)

Running time: 8:35 mins.
Removal of water from thermally stable solids by suction and oven heating; removal of water from thermally unstable compounds using a desiccator including: the use of desiccator cabinets, choosing desiccants, the safe use of a vacuum desiccator; removal of water from liquids using a selection of drying agents and the removal of drying agent; drying gases using molecular sieve and a drying tower and including the safe use of simple anhydrous calcium chloride charged drying tubes.

INFRARED SPECTROSCOPY OF SOLIDS (Programme 5.1; Basic 5.1; Practical 5.1)

Running time: 9:42 mins.
Discussion of sampling techniques; demonstration of the potassium bromide disc technique including: storage and handling of potassium bromide, using a mortar and pestle to mix sample and potassium bromide, disc pressing using a hydraulic press, removal of the resulting sample disc and transferring it to a sample holder; demonstration of the Nujol mull technique including: choosing the alkali halide plates, estimating quantities and preparing a mull, placing mull on alkali halide plates, and cleaning alkali halide plates with non-aqueous solvent, care of the plates.

INFRARED SPECTROSCOPY OF LIQUIDS (Programme 5.2; Basic 5.2; Practical 5.2)

Running time: 4:26 mins.
Obtaining a simple infrared spectrum of pure compound including: handling alkali halide plates, adding liquid between the alkali halide plates, mounting the plates in a plate holder; obtaining infrared spectra of dilute solutions including: the choice of spectroscopic grade solvent, filling cells with solution, mounting cells in a spectrophotometer, and cleaning and drying cells after use.

INFRARED SPECTROSCOPY OF GASES (Programme 5.3; Basic 5.3; Practical 5.3)

Running time: 5:16 mins.
Discussion of the infrared spectroscopy of gases; recording the infrared spectrum of a gas using a gas cell including: filling gas cell using carbon monoxide as an example of the purging method; loading the gas cell into spectrometer, obtaining a rotation-vibration spectrum, and flushing the gas cell with nitrogen gas to clean it. Appendix on the use of a vacuum line to fill a a gas cell if the gas is valuable, e.g. a deuterated sample, or highly absorbing so that only a low pressure is needed.

ULTRAVIOLET AND VISIBLE SPECTROSCOPY (Programme 5.4; Basic 5.4; Practical 5.4)

Running time: 4:54 mins.
Brief description of uv/visible absorption spectra; obtaining uv/visible spectra including: selecting a suitable spectroscopic solvent, making up samples, care of matching cuvettes, adding sample solution and reference solution to the cuvettes, locating cuvettes in a double beam spectrometer; tips if sample solutions bands are too strong or too weak. Appendix on the comparison of spectra for diphenylbutadiene, diphenylhexatriene, and diphenyloctatetraene.

PREPARING SAMPLES FOR NMR SPECTROSCOPY (Programme 5.5; Basic 5.5; Practical 5.5)

Running time: 5:38 mins.
Description of the materials and methods for proton nmr spectroscopy, e.g. deuterated solvents and nmr tubes; obtaining an nmr spectrum in a deuterated solvent including: selecting a suitable solvent and using a non-deuterated solvent for solubility testing, cleaning a tube, making up a sample, in situ filtration of a sample solution using cotton wool and a Pasteur pipette, inserting a sample tube into a spinner, various types of instrument; obtaining a typical spectrum; nmr spectra for other nuclei.

ASSEMBLING APPARATUS (Programme 6.1; Microscale 1.1; Practical 6.1)

Running time: 4:17 mins.
Introduction to microscale apparatus: reaction containers, magnetic stirring, setting up a reflux, use of Teflon tape to join glassware, and assembling apparatus; protection against moisture including: anhydrous calcium chloride tubes, silicon rubber septum caps, and hypodermic needles. Appendix on using apparatus with screw-capped couplings.

WEIGHING AND MATERIAL TRANSFER (Programme 6.2; Microscale 1.2; Practical 6.2)

Running time: 6:45 mins.
Use of a four decimal place balance to weigh materials; procedures for transferring and weighing solids and liquids; transfer using calibrated pipettes; transferring material using the manual variable-volume dispensing pipette; transferring material using a graduated 1cm3 pipette; transfers using syringes; discussion on the need to use syringes when handling air and moisture sensitive compounds including: inserting a needle, using a balloon filled with inert gas, and inserting a syringe into a stock liquid con tainer.

HEATING SAMPLES (Programme 6.3; Microscale 1.3; Practical 6.3)

Running time: 1:27 mins.
Introduction to heating methods; heating samples on a sand bath including: using a hotplate and a sand bath, using a thermometer to determine the bath temperature, exploitation of the inherent temperature gradient of a sand bath to effect gentle or vigorous heating.

GRAVITY FILTRATION (Programme 6.4; Microscale 1.4; Practical 6.4)

Running time: 1:25 mins.
Use of a Pasteur pipette including: lightly plugging a shortened-tip Pasteur pipette with cotton wool, how to shorten a Pasteur pipette tip, filtering, using extra solvent to rinse the pipette so as to ensure maximum recovery of sample.

SUCTION FILTRATION (Programme 6.5; Microscale 1.5; Practical 6.5)

Running time: 2:42 mins.
Use of a Hirsch funnel to isolate product from a reaction or recrystallisation including: assembling a Hirsch funnel, choosing and operating a source of vacuum, adding suspended solids to the funnel, filtering and washing the solid with filtrate, drying a sample under vacuum in side-arm test tube.

EXTRACTION AND PARTITION (Programme 6.6; Microscale 1.6; Practical 6.6)

Running time: 6:56 mins.
Introduction to microscale solvent extraction using a Pasteur pipette; mixing solvent layers using a pipette; removing the bottom or top layers; extracting an immiscible organic solid from an aqueous solution using ethyl ethanoate(acetate); removing inorganic impurities; drying extracts with anhydrous magnesium sulphate; removing the drying agent; isolating the product by boiling off the solvent using a sand bath.

DISTILLATION AT ATMOSPHERIC PRESSURE (Programme 6.7; Microscale 1.7; Practical 6.7)

Running time: 2:54 mins.
Introduction to the Hickman still which combines the functions of a condenser and a receiving flask; distillation process including: heating on a sand bath, transferring liquid to the flask using a Pasteur pipette, making secure joints using Teflon tape, placing the still in the sand bath, collecting the condensate from the still using a Pasteur pipette, the shut down procedure.

DISTILLATION OF HIGHER BOILING LIQUIDS (Programme 6.8; Microscale 1.8; Practical 6.8)

Running time: 2:00 mins.
Discussion of the options if it is suspected that the desired distillate may have too high a boiling point for atmospheric pressure distillation; insulating the flask with cotton wool, glass wool or aluminium foil; carrying out the distillation at reduced pressure including: assembling the apparatus, choosing a source of vacuum, insulating the flask, collecting the distillate from the still and the shutdown procedure.

THIN LAYER CHROMATOGRAPHY (Programme 7.1; Basic 6.1; Practical 7.1)

Running time: 6:42 mins.
Introduction to thin layer chromatography: the chromatography plate and choice of eluting solvent; carrying out the TLC process including: marking the plate, using a capillary tube to spot the plate, using a filter paper to saturate the atmos phere in the "tank" with solvent, adding solvent and plate to the "tank", the separation, removal of plate from the "tank" and subsequent drying; detecting spots using the naked eye, ultraviolet light, staining with iodine or dipping and spraying; interpreting the results; monitoring reactions; calculating R f values.

COLUMN CHROMATOGRAPHY (Programme 7.2; Basic 6.2; Practical 7.2)

Running time: 6:36 mins.
Introduction to column chromatography with the use of TLC to pre-select the solvent system; selection and preparation of columns including: using a column with a frit or a glass wool plug, adding solvent/silica gel slurry to a column followed by recycling of solvent and elimination of air bubbles, using compressed air to force fresh solvent through ready for adding sample, adding sample; chromatography process: collection of eluent, analysis of eluent fractions by TLC, combination of eluent fractions and subsequent concentration by evaporation using a rotary evaporator.

ION EXCHANGE CHROMATOGRAPHY (Programme 7.3; Basic 6.3; Practical 7.3)

Running time: 8:15 mins.
Introduction to ion exchange chromatography; preparation of ion exchange resin by suspension in deionised water; preparation of an ion exchange column; addition of resin slurry to column; draining off excess water; regeneration of old exchange resin by adding 6M hydrochloric acid followed by addition of deionised water and testing of washings with an indicator; ion exchange chromatography: addition of sample, eluting and testing eluent with indicator, and titrating the acid eluent with standard alkali using an indicator.

GAS CHROMATOGRAPHY (Programme 7.4; Basic 6.4; Practical 7.4)

Running time: 7:43 mins.
Introduction to the gas chromatograph: packed and capillary columns, ovens, mobile phase/carrier gas e.g. nitrogen or helium; operating the gas chromatograph: setting the injector- port and oven temperatures, dissolving the sample in a solvent(diethyl ether), injecting the sample onto column, using a gas syringe and loop to present gaseous samples; detection of eluents and brief description of detectors available; discussion of retention times and their signifi cance; identification of unknown compounds.

USING BALANCES (Programme 8.1; Basic 7.1; Practical 8.1)

Running time: 9:10 mins.
Introduction to weighing in the laboratory: the general purpose balance, the analytical balance, containment vessels, location of balances, levelling a balance; using a general purpose balance: weighing reagents and what to do if a spillage occurs; using an analytical balance for both solids and liquids: "quantitative transfer" dealing with tongs, tweezers and gloves so as to avoid contamination, "weighing by difference" where "quantitative transfer" is inappropriate, and the "absolute weights" method as used in gravimetric analysis and ashing where items are weighed to "constant weight".

USING A PIPETTE (Programme 8.2; Basic 7.2; Practical 8.2)

Running time: 9:16 mins.
Introduction to pipettes and fillers: the volumetric pipette and measuring pipette, pi-pump and 3 valve rubber bulb pipette fillers, and some safety precautions; using the volumetric pipette with a pi-pump filler: rinsing and filling the pipette, using the calibration mark, transferring an aliquot to a receiving vessel; using a volumetric pipette with a 3 valve rubber bulb pipette filler as per the pi-pump filler including what to do if the valve leaks; using the measuring pipettes.

USING A BURETTE (Programme 8.3; Basic 7.3; Practical 8.3)

Running time: 4:32 mins.
Introduction to burettes: capacity, stopcocks both greased and PTFE types; checking for leaking stopcocks; rinsing a burette; filling a burette; removal of air bubbles and air trapped in the tip; filling and using a burette.

MAKING UP SOLUTIONS (Programme 8.4; Basic 7.4; Practical 8.4)

Running time: 7:04 mins.
Choosing a volumetric flask e.g. the question of the size of flask versus accuracy; storing standard stock solutions; using a volumetric flask in determination of copper in a copper salt: drying and cooling the copper salt in a desiccator, weighing to four decimal places, adding reagents and water with perhaps heating to effect dissolution, transferring cooled solution to volumetric flask, making up to a calibration mark, and mixing by inversion of the flask; examples of different ampoules for standard stock solutions; diluting stock solutions.

GRAVIMETRIC ANALYSIS (Programme 9.1; Basic 8.1; Practical 9.1)

Running time: 11:02 mins.
Outline of a typical procedure for gravimetric analysis e.g. the nickel content in a sample of nickel salt; step by step procedure: drying sintered glass crucibles, quantitative trans fers of liquid or solid samples to reaction vessels, addition of reagents to form the nickel-dimethylglyoxime precipitate, testing for complete precipitation, digesting the precipitates, weighing the cooled dried crucibles, transferring and filtering the precipitate, drying and weighing the crucibles and precipitate to constant weight including the use of an oven and a desiccator.

ELECTROGRAVIMETRIC ANALYSIS FOR METALS (Programme 9.2; Basic 8.2; Practical 9.2)

Running time: 8:30 mins.
Introduction to a typical electrogravimetric analysis, e.g. copper in a copper salt; description of the procedure: weighing the platinum electrode to constant weight, weighing the copper salt quantitatively, dissolving it in distilled water, acidifying the solution with sulphuric acid, setting up a stirrer, mounting and connecting the electrodes, applying voltage at constant current to the electrogravimetric cell, testing for complete deposition, washing the platinum electrode using acetone and drying it to constant weight; procedure for mixed metal solutions.

KJELDAHL DETERMINATION OF NITROGEN (Programme 9.3; Basic 8.3; Practical 9.3)

Running time: 10:01 mins.
Introduction; the "simple" Kjeldahl method for determining nitrogen: weighing hexammine cobalt trichloride to four decimal places, transfer to the digestion flask, adding dilute hydrochloric acid and indicator to the receiving flask, adding dilute sodium hydroxide to the digestion flask, heating the digestion flask, adding extra water to maintain the level in the digestion flask, titrating the distillate in receiver flask with standard alkali to calculate nitrogen content; "vigorous" Kjeldahl digestion: using heat and concentrated sulphuric acid to break down compounds followed by the "simple" method as before.

MEASURING AND CONTROLLING TEMPERATURE (Programme 10.1; Basic 9.1; Practical 10.1)

Running time: 7:54 mins.
Introduction; using liquid in glass thermometers: mercury thermometers, accuracy of mercury thermometers, Beckman thermometer, limitations of the mercury thermometer, low temperature pentane thermometers, immersion depths for quantitative work, use in Quickfit apparatus, repairing a broken bead using solid carbon dioxide to decrease the volume of liquid in the bulb; electrical temperature measurement: thermocouple and meter, bimetallic junctions, the thermistor, non-contact thermometers; controlling temperatures, using constant-temperature bath for kinetic studies.

DETERMINATION OF MELTING TEMPERATURE (Programme 10.2; Basic 9.2; Practical 10.2)

Running time: 8:12 mins.
Introduction to melting temperatures: purity and identity; determination of melting temperature: grinding samples, transferring a solid to a melting temperature tube, using an aluminium block apparatus; mixed melting temperature determination using two different substances. Appendix on sealing melting temperature tubes: normal tubes, tubes for samples which sublime and decompose on heating. Appendix on using a Hot Stage Microscope for very small amounts of sample.

DETERMINATION OF BOILING TEMPERATURE (Programme 10.3; Basic 9.3; Practical 10.3)

Running time: 2:42 mins.
Description of boiling temperature; determination of boiling temperatures using melting temperature apparatus: heating melting temperature tube over bunsen flame to form a very fine capillary tube, breaking and sealing of the capillary tube, placing the capillary tube and liquid in a melting temperature tube, loading into melting temperature apparatus, recording the boiling temperature - the temperature at which a continuous stream of bubbles form on heating and when the bubbles just stop forming on cooling.

DETERMINING A LIQUID/LIQUID PHASE DIAGRAM (Programme 10.4; Basic 9.4; Practical 10.4)

Running time: 3:44 mins.
Introduction to liquid/liquid phase diagrams; determining the phase diagram for the phenol/water system: preparing a range of known composition mixtures by weighing the phenol into small test tubes and pipetting in the water, placing tubes in turn inside a large water filled tube, adding a thermometer inside the phenol water mixture, heating the water jacket using a micro bunsen burner, noting the temperature at which miscibility occurs on heating together with cloudiness upon cooling; plotting a phase diagram.

DETERMINING A SOLID/SOLID PHASE DIAGRAM (Programme 10.5; Basic 9.5; Practical 10.5)

Running time: 2:46 mins.
Introduction to solid/liquid phase diagrams; determining the phase diagram of the acetamide/p-nitrophenol system: preparing a range of known composition mixtures by weighing the acetamide and p-nitrophenol into a small test tubes, heating each tube until the solid melts and then placing it inside a conical flask to cool, noting the temperature at which solidification occurs; plotting a phase diagram.

THIN LAYER CHROMATOGRAPHY (Programme 11.1; Microscale 2.1; Practical 11.1)

Running time: 6:42 mins.
Introduction to thin layer chromatography: choosing the chromatography plate and the eluting solvent; carrying out the TLC process: marking the plate, spotting with a fine drawn capillary tube, repeat spotting for very dilute solutions, using a filter paper to saturate the atmosphere in the "tank" with solvent, adding the solvent and plate to the "tank", the separation, removal of the plate and subsequent drying; detecting spots by the naked eye, ultraviolet light, staining with iodine or dipping and spraying; interpreting results; monitoring reactions, measuring Rf values.

COLUMN CHROMATOGRAPHY (Programme 11.2; Microscale 2.2; Practical 11.2)

Running time: 9:56 mins.
Comparison of microscale column chromatography with conventional chromatography; preparing the column and reagents including: shortening the tip of a Pasteur pipette, inserting a cotton wool plug, clamping and filling with first some sand then dry silica, adding solvent and removing air bubbles and cracks; loading the sample; eluting the fractions; identification of the separated components via TLC; recovery of products.

GAS CHROMATOGRAPHY (Programme 11.3; Microscale 2.3; Practical 11.3)

Running time: 4:32 mins.
Introduction to gas chromatography: columns, oven, mobile phase/carrier gas e.g. nitrogen or helium; operating the gas chromatograph: setting the injector-port and oven temperatures, dissolving the sample in a solvent(diethyl ether), injecting the sample onto the column, detection of eluents; discussion of retention times and their significance; identification of unknown compounds.

PREPARATION OF A GRIGNARD REAGENT (Programme 11.5; Microscale 2.4; Practical 11.5)

Running time: 8:17 mins.
Assembling apparatus and adding initial reactants including: sealing the condenser with a rubber septum, fitting it with a hypodermic needle and drying tube; preparation of a Grignard reagent: adding further bromobenzene, refluxing, injecting propiophenone using a needle and syringe followed by further refluxing; purification of products: reaction with dilute sulphuric acid, separation and extraction of the aqueous and ether layers, drying the ether layer, filtering off the drying agent, boiling off the ether.

RECRYSTALLISATION (Programme 12.1; Microscale 3.1; Practical 12.1)

Running time: 8:46 mins.
Factors governing a successful recrystallisation; the recrystallisation process: solvent test using heated samples in sand bath, filtration through a pre-heated shortened Pasteur pipette, reducing solvent volume using a sand bath, cooling and crystallisation of product, filtration of product under suction using a Hirsch funnel, washing crystals with cold solvent, and drying the crystals by suction or under vacuum in the side-arm test tube.

RECRYSTALLISATION USING A CRAIG TUBE (Programme 12.2; Microscale 3.2; Practical 12.2)

Running time: 5:12 mins.
Introduction to the Craig tube; recrystallisation using the Craig tube: dissolving the sample in a hot solvent, filtration through a shortened Pasteur pipette, collecting the filtrate and washings in a Craig tube, reducing the solvent volume on sand bath, capping the Craig tube, cooling to promote crystallisation, inverting and placing in a pre-balanced centrifuge, recovering the crystals after centrifuging, washing and drying crystals; dealing with very finely divided crystals.

DETERMINATION OF BOILING TEMPERATURE (Programme 12.3; Microscale 3.3; Practical 12.3)

Running time: 2:42 mins.
Description of boiling temperature; determination of boiling temperatures using melting temperature apparatus: heating a melting temperature tube over bunsen flame to form a very fine capillary tube, breaking and sealing the capillary tube, placing the capillary tube and liquid in melting temperature tube, loading the assembly into a melting temperature appar atus, noting the boiling - the temperature at which a continuous stream of bubbles form on heating and when the bubbles just stop forming on cooling.

DETERMINATION OF MELTING TEMPERATURE (Programme 12.4; Microscale 3.4; Practical 12.4)

Running time: 5:44 mins.
Introduction to melting temperatures: purity and identity; determination of melting temperature: grinding a sample, transferring a solid to a melting point tube, using an aluminium block melting point apparatus; mixed melting temperature determination of melting temperature using two different substances. Appendix on using a Hot Stage Microscope for very small amounts of sample.

INFRARED SPECTROSCOPY OF SOLIDS (Programme 12.5; Microscale 3.5; Practical 12.5)

Running time: 5:00 mins.
Discussion of sampling techniques; demonstration of the potassium bromide disc technique including: storage and handling of potassium bromide, using a pestle and mortar to mix sample and potassium bromide, disc pressing using a bench- mounted hand press, mounting in the die assembly in the infrared spectrometer, cleaning the die by dissolving the disc with water, drying the die in an oven; demonstration of the Nujol mull technique including: handling alkali halide plates, estimating quantities and preparing a mull, placing the mull on the alkali halide plates, cleaning plates with a non- aqueous solvent.

INFRARED SPECTROSCOPY OF LIQUIDS (Programme 12.6; Microscale 3.6; Practical 12.6)

Running time: 1:58 mins.
Obtaining an infrared spectrum of liquid including: handling alkali halide plates, adding liquid between alkali halide plates, mounting the plates in a plate holder; obtaining a spectrum; dealing with strongly absorbing samples by wiping one plate clean and reducing the thickness of the liquid film; cleaning and care of alkali halide plates.

DOING A TITRATION (Programme 13.1; Basic 10.1; Practical 13.1)

Running time: 5:09 mins.
Introduction to titrations; preparing the burette; preparing the titration flask including pipetting the reagents; doing a preliminary or "rough" titration; doing an accurate titration including the "half-drop" technique; using an automatic titrator.

SOME COMMON END POINTS (Programme 13.2; Basic 10.2; Practical 13.2)

Running time: 6:19 mins.
Introduction to using indicators in titrations; the format for showing endpoints in this clip; endpoint demonstrations: methyl red, methyl orange, screened methyl orange, phenolphthalein, bromothymol blue, bromocresol green eriochrome black T, murexide, fluorescein, potassium chromate, ammonium iron(III) sulphate, starch or starch substitute, self- indicating immiscible solvents, sodium diphenylamine sulphonate, ferroin and self-indicating potassium permanganate.

POTENTIOMETRIC TITRATIONS (Programme 13.3; Basic 10.3; Practical 13.3)

Running time: 17:32 mins.
General introduction to potentiometric titrations (0:39 min); description of pH titrations (8:47 min) including: comparison of indicator and instrumental methods, using a Ph meter, calibrating the system, doing an accurate Ph titration, examples of graphs for different types of acids and bases and applications to multiple endpoints; descriptions of oxidation- reduction titrations (4:33 min) and silver halide titrations (3:20 min) including: introductions, preparing the systems, taking readings, caring for the electrodes and plotting the results.

USING A BOMB CALORIMETER (Programme 14.1; Basic 11.1; Practical 14.1)

Running time: 13:15 mins.
Introduction to thermochemical measurements; description of a typical bomb calorimeter; the calibration procedure; preparing the bomb for firing; firing the bomb; plotting the results; correction factors; sampling techniques for solid and liquid samples.

USING A DEWAR CALORIMETER (Programme 14.2; Basic 11.2; Practical 14.2)

Running time: 5:20 mins.
Introduction to Dewar calorimetry; description of a typical Dewar calorimeter; preparing for a run; obtaining readings; interpreting the data; dealing with corrections.

DETERMINATION OF ENTHALPY OF NEUTRALISATION (Programme 14.3; Basic 11.3; Practical 14.3)

Running time: 9:20 mins.
Introduction to the use of Dewar calorimetry for measuring enthalpies; preparing for calibrating the calorimeter; taking calibration readings; determining corrections for dilution effects; obtaining results for samples; interpreting the data.

OXIDATION OF IODIDE BY HYDROGEN MEROXIDE (Programme 15.1; Basic 12.1; Practical 15.1)

Running time: 5:51 mins.
Background to the reaction which is known as "the iodine clock reaction"; defining the experimental conditions; making up solutions; carrying out the experiment; plotting the results; determining the importance of other variables.

OXIDATION OF IODIDE BY POTASSIUM PEROXYDISULPHATE (Programme 15.2; Basic 12.2; Practical 15.2)

Running time: 5:40 mins.
Background to the kinetic determinations; preparing the equipment; making up the reagents; carrying out kinetic runs; plotting the results; obtaining activation energies; determining the importance of other variables.

IODINATION OF KETONES (Programme 15.3; Basic 12.3; Practical 15.3)

Running time: 8:45 mins.
Background to halogenation reactions; the importance of controlling temperature; preparing solutions; setting up the uv/visible spectrometer; carrying out the experiment; plotting the results; obtaining the kinetic parameters.

MEASURING SOLUTION PARTITION COEFFICIENTS (Programme 15.4; Basic 12.4; Practical 15.3)

Running time: 5:56 mins.
Background to the phenomenon of partitioning material between solvents with differing polarities; determining saturation concentrations for iodine in water and toluene; carrying out a partition experiment using the titration method; using an alternative spectrophotometric method.

COLORIMETRIC ANALYSIS (Programme 15.5; Basic 12.5; Practical 15.5)

Running time: 3:37 mins.
Introduction to colorimetric measurements; preparing solutions; setting up a calibration procedure; measuring unknown samples; plotting the results; caring for solution cells.

USING GALVANIC CELLS (Programme 16.1; Basic 13.1; Practical 16.1)

Running time: 4:09 mins.
Introduction to the components of galvanic cells; examples of different types of electrodes; caring for electrodes; calibration of digital voltmeters; using salt bridges.

DETERMINATION OF STANDARD ELECTRODE POTENTIALS (Programme 16.2; Basic 13.2; Practical 16.2)

Running time: 4:46 mins.
Background to measuring standard electrode potentials; preparing the sample cell; preparing the reference cell; using a salt bridge; using digital voltmeters; what do if readings drift; taking measurements; caring for the electrodes; plotting the results.

ELECTROCHEMICAL METHOD FOR DETERMINING SOLUBILITY PRODUCTS (Programme 16.3; Basic 13.3; Practical 16.3)

Running time: 2:34 mins.
Introduction; preparing the sample solution; preparing the reference solution; setting up the measuring system; taking readings; handy hints for obtaining good data; obtaining solubility products for a variety of AgX salts.

USING ELECTROCHEMICAL CELLS TO DETERMINE THERMODYNAMIC PARAMETERS (Programme 16.4; Basic 13.4; Practical 16.4)

Running time: 2:06 mins.
Introduction to the thermodynamic effects on electrode potentials; assembling a "button cell" (zinc/silver oxide alkali cell) and electrochemical circuitry; taking readings; plotting the results.

USING CONDUCTIVITY CELLS (Programme 16.5; Basic 13.5; Practical 16.5)

Running time: 3:19 mins.
Introduction to the components of dipping conductivity cells; setting up the equipment; measuring the cell constant; measuring the conductivities of sample solutions; caring for dipping electrodes.

CONDUCTIOMETRIC TITRATIONS (Programme 16.6; Basic 13.6; Practical 16.6)

Running time: 6:05 mins.
Introduction to conductiometric titrations; preparing the sample solutions; testing the system; setting up the burette; taking measurements; caring for the electrode; plotting the results.

USING AN AUTOMATIC TITRATOR (Programme 16.7; Basic 13.7; Practical 16.7)

Running time: 3:57 mins.
Background to multiple sampling techniques; setting up an automatic titrator; carrying out a typical titration; plotting the results; manipulating the data, e.g. 1st derivative plots; shut-down procedure.

DETERMINATION OF THE MOLECULAR WEIGHT OF GASES (Programme 17.1; Basic 14.1; Practical 17.1)

Running time: 12:12 mins.
Introduction and safety aspects; description of a typical vacuum line; starting up the vacuum line; pumping out the line; checking for leaks; connecting the sample trap; attaching the molecular weight bulb; weighing empty and filled bulbs; recovering the bulb sample; shut-down procedure.

MEASURING THE NO2/N2O4 EQUILIBRIUM (Programme 17.2; Basic 14.2; Practical 17.2)

Running time: 10:00 mins.
Introduction to equilibrium processes; description of the vacuum line; evacuating the vacuum line; finding the null point of the spiral gauge; taking measurements; shut-down procedure; plotting the data.

MEASURING THE SATURATED VAPOUR PRESSURE OF A LIQUID AT VARIOUS TEMPERATURES (Programme 17.3; Basic 14.3; Practical 17.3)

Running time: 6:15 mins.
Introduction; how an isoteniscope works; evacuating the system; setting up the isoteniscope; taking measurements; what to do if a suck-back occurs; collecting data; shut-down procedure; plotting the data.

USING A FORTIN BAROMETER (Programme 17.4; Basic 14.4; Practical 17.4)

Running time: 1:28 mins.
Introduction to and description of a Fortin barometer; making adjustments; taking readings; correcting for temperature effects.

USING A POLARIMETER (Programme 18.1; Basic 15.1; Practical 18.1)

Running time: 8:25 mins.
Introduction to polarimetry; setting up the instrument; assembling sample tubes; filling a sample tube; recording the null position for the solvent; obtaining the angular reading for a sample solution; measuring time-dependent phenomena.

DETERMINATION OF THE REFRACTIVE INDEX (Programme 18.2; Basic 15.2; Practical 18.2)

Running time: 8:20 mins.
Introduction to the Abbe refractometer; setting up the instrument; calibration using distilled water; measuring the refractive index of a liquid sample; dealing with dark liquids; the shut-down procedure; correlating refractive indices with structure and other physical data; other types of refractometers; measuring refractive indices for solids.

MEASURING RATES OF RADIOACTIVE DECAY (Programme 18.3; Basic 15.3; Practical 18.3)

Running time: 6:43 mins.
Introduction to radioactive processes; description of the equipment to measure decay rates; measuring a sample; interpreting the data, obtaining a "half-life", the shut-down procedure.

GAS PHASE ELECTRONIC SPECTRA (Programme 18.4; Basic 15.4; Practical 18.4)

Running time: 6:10 mins.
Introduction; description of a simple spectrometer; description of a constant deviation spectrometer; calibration of a constant deviation spectrometer; measuring the emission spectrum of sodium; measuring the absorption spectrum of iodine.

USING A FLAME PHOTOMETER (Programme 19.1; Basic 16.1; Practical 19.1)

Running time: 10:15 mins.
Introduction; the start-up procedure for a typical flame photometer; selecting a filter; setting up the instrument; calibrating the instrument; measuring an unknown sample; the shut-down procedure; dealing with partially dissolved samples; handling the data.

USING AN ATOMIC ABSORPTION SPECTROMETER (Programme 19.2; Basic 16.2; Practical 19.2)

Running time: 7:12 mins.
Introduction to a typical atomic absorption spectrometer; the start-up procedure; selecting a lamp; choosing the analysis wavelength; calibrating the instrument; measuring a sample; handling the data; the shut-down procedure.

THERMOGRAVIMETRIC ANALYSIS (Programme 19.3; Basic 16.3; Practical 19.3)

Running time: 11:01 mins.
Introduction to thermal processes; description of a typical instrument; preparing crucibles; the start-up procedure; doing a trial run; characteristic features of TGA traces; inspecting residues; doing an accurate run; using a first derivative plot to simplify interpretation; the shut-down procedure.