Understanding Chemistry



The Site


The site was originally intended to meet the needs of UK A level chemistry students, but it has been widened over the years to cover material on all the UK-based syllabuses including A level, IB, Scottish Advanced Highers and Cambridge International. In fact it is now being used by people on equivalent (16 to 18 year old) courses worldwide and by students at the beginning of university level courses.

I started by concentrating on the bits that textbooks tend to do too quickly and that students often find difficulty with. My over-riding aim is to try to increase your understanding of these difficult bits so that you gain confidence.

I have since added lots of factual content, but always with a concentration on understanding. I'm simply not interested in the "learn this parrot-fashion and you will pass" approach - it is much more of a slog than taking a bit of time to understand what is going on.

As of July 2016, I am unlikely to add anything new to Chemguide, apart from the occasional bit of maintenance to make sure that it is as accurate as possible.

Missing or incomplete topics

There are some things that you won't find covered in complete detail (or sometimes won't find at all) on Chemguide - for example:

  • Calculations. There are some calculations missing completely, and others where all you will find is a minimal introduction. That is because you will find what you need to know at this level in my chemistry calculations book (see link below). I need the income from sales of my books both to live and to subsidise the running costs of this site.

  • Crude oil (petroleum) distillation: boring, and all over the web!

  • Environmental chemistry: all over the web, especially on the excellent US Environmental Protection Agency site.

  • Uses for things: easy to find, and largely boring!

Helping yourself

To get the best from the site you must have a clear idea of what you need to know. You will often find comments suggesting that you should refer to your syllabus or to recent exam papers. It is important that you have these to hand.

Students on UK-based courses can easily download syllabuses from their Examiners, and should be able to find other useful things on those websites. You can find links to these sites via the Main Menu.

If you are working in another examination system, you still need to know exactly what is expected of you, but will have to find that information for yourself.

About the author

Jim Clark

  • is a Cambridge graduate with over 30 years of teaching experience at this level.

  • was Head of Chemistry and then Head of Science at Truro School in Cornwall.

  • took early retirement in 1997 and has since concentrated on writing.

  • is the author of Calculations in AS/A Level Chemistry published by Longman (September 2000). Follow the link to find out more about the book.

  • is the author of Longman GCSE Chemistry published by Longman (May 2002). This is now out of print.

  • is joint author (with Ray Oliver) of Longman Chemistry for CXC (published Jan 2004). The second edition is called Longman Chemistry for CSEC. Both editions were adapted by Ray Oliver from my GCSE book.

  • is joint author (with Ray Oliver) of Longman Chemistry for IGCSE (published June 2005). This book was approved by Edexcel International for use with their IGCSE Chemistry syllabus, and was also adapted by Ray Oliver from my GCSE book. Beware that this book is no longer appropriate for Edexcel International GCSE examinations from 2011 onwards, and has been out of print for some time. Even if someone gives you a free copy, don't use it!

  • is the author of Edexcel IGCSE Chemistry published June 2009. This is for the syllabus which was examined for the first time in 2011. This link will take you to support pages for the book in another part of Chemguide.

  • is joint author (with Steve Owen and Rachel Yu) of Edexcel International GCSE (9-1) Chemistry published in 2017. This is for the syllabus which will be examined for the first time in June 2019. This link will take you to support pages for the book in another part of Chemguide.

Contacting the author

  • I am no longer prepared to answer any chemistry questions from anyone, unless they relate to an error that you have found on Chemguide. You will find my reasons for this in the questions and comments section (link below).

  • If you are a student, and think you may have found an error on the site, could you please read this page before you contact me.

  • If you have questions about other things relating to the site, they may have been answered in my questions and comments section.

  • I get a steady trickle of requests from people who want to buy the site. Chemguide isn't for sale and won't be in the future either. From now on, I shan't reply to such e-mails.

  • If you want to suggest a page or site that I might like to link to on Chemguide's links page, please read this page first.

Copying from this site

You may use the information on this site in any way you wish - including making multiple copies for other people's use - provided that

  • you make clear where the information came from;

  • nobody makes any financial gain from it.

Go to Main Menu . . .

© Jim Clark 2004 (last modified June 2019)