Modern Chemical Techniques (Royal Society of Chemistry)

Reviewed by David R. Everett Department of Chemistry, Felsted School, Felsted, Dunmow, Essex, England CM6 3JG dre@felsted.rmplc.co.uk

Modern Chemical Techniques The Royal Society of Chemistry, 1996. Running time 50 minutes. Price 29 pounds sterling. VHS format (PAL only). (Complements the book Modern Chemical Techniques, ISBN 1 87034 319 0.)

The high-school curriculum now includes techniques such as infrared, UV–vis, and NMR spectroscopy, chromatography, and mass spectrometry. Some teaching syllabi, notably the Salters' Advanced Chemistry in the United Kingdom, include techniques such as atomic absorption spectroscopy. Unfortunately, very few schools have the resources to teach these techniques in a hands-on manner. A few lucky schools may acquire redundant hardware from industry, but by its very nature, this equipment is unlikely to be at the cutting edge of modern technology.

This video aims to plug the gap and give students a more realistic experience of how modern chemical techniques are used. The twelve techniques covered are UV–vis spectroscopy, IR spectroscopy, atomic absorption spectroscopy, NMR spectroscopy, mass spectrometry (MS), X-ray crystallography, elemental microanalysis, electron probe microanalysis, gas chromatography (GC), HPLC, gel electrophoresis, and capillary electrophoresis.

Each technique is covered on the tape by a separate segment that is intended to be used when teaching that technique. Each segment starts with an overview of the equipment and mentions the uses to which it can be put. The hardware is then shown in highlighted sections as the function of each part of the apparatus is explained. With some of the techniques, animations are used to show what is happening to the chemical species involved in the technique. Sample preparation is also shown and explained. The role of computers in handling samples, and collecting and analyzing data is also covered where relevant.

The background commentary is factual and carefully expounded; it alternates between two commentators. This provides some variety, but is not really necessary if the tape is used in short extracts, as intended. These commentaries are disembodied background voices, somewhat flat in tone, explaining what is seen on the screen. A more lively approach might have been achieved without loss of continuity if the machine operators were seen to be giving the commentaries. By the same token, the lack of background laboratory or instrumental noise in most of the segments avoids distraction but produces a rather sterile presentation. Some interest is provided by showing specimens under test; for example in the section on electron probe microanalysis, a sample of bone chip is seen under examination at the Royal National Orthopaedic Hospital at Stanmore, Middlesex.

Each video segment lasts approximately 5 minutes, and thus the amount of information given must be limited. The tape was not intended to be an instruction manual for any method, but rather as a series of visual aids to complement teaching. As such, it serves its purpose well. The sections covering UV–vis, IR, and MS techniques are particularly impressive, although the section covering NMR gave little information on how different chemical shifts are used.

Background information on UV–vis, IR, NMR, MS, GC, and HPLC can be found in a resource book, Modern Chemical Techniques, written by Ben Faust and published by the Royal Society of Chemistry. This book is designed to accompany the videotape as a resource for teachers who may wish to update their knowledge of techniques that have been introduced or refined since they studied chemistry at a college or university. An additional publication, entitled More Modern Chemical Techniques, has been prepared by another School Teacher Fellow of the RSC, Ralph Levinson, and is due to be published by the RSC early in 1998. Having been involved in reading drafts of this publication, I can indicate that it will cover the other techniques shown on the video, and give a similar level of background material for teachers to that supplied by Ben Faust in his book.

I have found this tape a very useful addition to the resources available to a teacher at the A-level, and it brings to life techniques that could only be covered theoretically or by visits to industry or university departments. Such visits do take place, but their timing is unlikely to coincide with the teaching of the topics; it is in this context that the video is most useful. It is less likely to be as useful in undergraduate teaching, since many University courses include hands-on teaching of many of the techniques during practical classes. However, some departments would not teach all these techniques, and the tape may still prove useful at this level.