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Looking back at 20 years of the MOLECULE OF THE MONTH website


Paul May (University of Bristol, UK)
Simon Cotton (University of Birmingham, UK)


The Molecule of the Month website administered from the University of Bristol, UK, is one of the longest running websites on the web (started Jan 1996).  As its name implies, each month a new article is posted describing a particular molecule, along with its history, science and numerous interesting anecdotes.  The aim of the site is to make chemistry accessible to non-scientific readers, and so the articles are written in an easy-to-read question-and-answer format, and illustrated with photographs, cartoons and structure diagrams, along with quotations from movie stars, rock songs and other snippets from popular culture.  The website has been of the pioneers for web innovations such as Chime, Chemsymphony and JMol.  As it comes up to its 20th anniversary, we shall look back at two decades of contributions from authors from all over the world, comment about the way the site has evolved over this time due to changing technology, and discuss what the future may hold for sites like these.

Looking back at 20 years of the MOLECULE OF THE MONTH website

The Internet/World Wide Web has been with us for just over 20 years and it is commonplace to say that it has revolutionised the ways in which we communicate with each other.

Nearly 20 years ago a group of chemistry academics in the UK were thinking about ways to use these new media to communicate the wonder of chemistry to a wider audience.  The original idea came from Henry Rzepa of Imperial College London, who brought together Karl Harrison of the University of Oxford and Paul May of the University of Bristol to try to produce regular, monthly articles showcasing important chemical substances, and hosting them on their department’s website.  The website linking these articles together became known as the Molecule of the Month (MOTM) website [1], with the first molecule (mauveine) appearing in January 1996 (which is so early that it’s actually before many University Chemistry departments even had their own departmental website!).

The MOTM page for May 2014 was about sucrose.

The original idea was that the 3 founders would each only write the occasional MOTM article; most of the content (it was hoped) would be written for us by willing volunteers from around the world.  This was broadly true for the first 5 years or so, with contributions coming from a whole range of authors drawn from across the globe.  Most have been from the University sector, but some have been written by chemists in industry, and some by schoolteachers and students, the youngest being 15 year old Layth Hendow, of Hull Collegiate School, Yorkshire, who wrote about Teflon [2].  Some of the earliest MOTM articles were short and rather basic.  But the more recent ones have been quite detailed essays, with scientific diagrams, videos, synthetic reactions schemes, more reminiscent of mini-review papers than web pages.

Other ‘molecule’ sites followed in their wake, such as one based at Virginia Commonwealth University in the USA, or at Prous in Spain, but gradually many of these have fallen by the wayside. Others have grown up in the blogging sector.  One of the issues that began to emerge around 2000 was that of legal liability for the content of the sites.  At Oxford and Bristol, we were getting undergraduate students to write small MOTM pages as web projects (originally sponsored with prizes by the RSC as part of their Exemplarchem project), the best of which were then becoming that month’s official MOTM.  An example of this is the MOTM page about capsaicin, written by the then Bristol undergraduate Matt Bellringer [3].  The issue was that the university was effectively publishing scientific documents that had been written by students, and potentially full of errors.  Even back then, the university lawyers began to worry whether the university might be laying itself open to litigation if someone read a factually incorrect MOTM written by a student, and then acted on this false information, e.g. if they tried to follow a synthesis recipe which led to an accident, or ingested a chemical they’d read was non-toxic, only to find the author hadn’t checked their facts properly!  In light of these worries, Karl Harrison decided to take all the Oxford MOTM pages off the Oxford University server, and place them onto an independent server operated by the company [4], and ensuring that all content was verified by him.  The main MOTM site, however, carried on regardless, except that all content became much more carefully vetted.  In fact, the only MOTM page that was ever withdrawn was one about sarin nerve gas (March 1999) because it contained rather too much detail about the precursors and the synthesis procedure than was deemed expedient – even though those details were freely available in the scientific literature (and still are available on Wikipedia and the wider internet).

As time passed, some of the innovations that accompanied the early web – like Chime or VRML (which allowed 3D structures to be displayed inside webpages) – have faded into history, but HTML versions have been the backbone of the Bristol site. Even though some users might not have Chime or Java installed to help them visualise some of the graphics, there has always been a HTML version “open to all”.

The MOTM page for February 2006 was about hemoglobin.

The emergence of Wikipedia has seen that develop as a free repository of factual information about chemicals, and there are also readily available databases of spectroscopic data (such as the Spectral Database for Organic Compounds, SDBS [5]).  Not long after Wikipedia became established, we saw a large drop in MOTM hits, and a reluctance for authors to write new MOTM pages.  After all, why would anyone bother reading a MOTM page when all the facts you could ever possibly want about every molecule are on Wikipedia? 

Original MOTMs often featured research advances of interest to the authors, and the style could be rather academic. What was needed was a change of style, to differentiate a MOTM article from a Wikipedia entry.  This was brought about by Simon Cotton’s first MOTM about tetraethyl lead in Jan 2001 [6].  The innovation was to write the article in a question-and-answer style, which chunked the information up into a series of short paragraphs, in the form of a curious student asking questions of a knowledgeable, patient, but long-suffering teacher.  Simon’s background as a “long-suffering” schoolteacher was ideal for this, and this style let a breath of fresh air into the tired MOTM format.  Nearly all the MOTMs nowadays use this style, and the MOTM articles have continued to be posted monthly, not a bad achievement after 20 years!  We try to aim at a level that is readily understood by a motivated 18-year old, and experience (and feedback) tells us that many adults from a non-scientific, even arts background find interesting content that they had not expected to encounter.  So many molecules are fantastic in terms of what they do.  The MOTM site compasses a vast range of them, found everywhere from foodstuffs to medicines; explosives to toxins.  It exists to convey a little of our contributors’ wonderment to a wide readership.  We don’t just concentrate on the facts, but try to weave an interesting story about the history of that month’s molecule, its role in modern society (including references to rock/pop music, Hollywood films/filmstars, TV programmes, historical figures, etc.) and its good and bad points.  For controversial molecules (DDT, thiomersal, bisphenol A, etc.) we try to remain neutral, tell both sides of the story, and let the reader make up their own mind.  After all, molecules are morally neutral until humans start to interact with them or use them.

Even within the first 5 years of the website, we’d started to notice that articles contributed by external authors and hosted on their websites were not as permanent as we’d hoped.  MOTMs would disappear, either because in the years since the article had been written the host server had been replaced, or the author had moved jobs, or in two cases because the authors had died and their webpages (and our precious MOTM article) deleted!  Luckily we’d made local backups of these pages, so simply switched the link.  But it made us worry about the permanency of the MOTM project.  After 20 years, we have nearly 240 MOTM articles, which include a wealth of data and information that would be a shame to lose, if say, Bristol University decided it no longer wished to host the site in future. 

Partly to get around this legacy issue, we decided to publish our favourite 60 or so MOTMs in a more long-lasting format – a paper book!  Selected articles were rewritten (in the Q&A style) to make them more accessible to a general audience, with less detailed chemistry (synthetic recipes, etc.) and more interesting anecdotes, ‘fun facts’, cartoons, and pictures, and these were collated and published in a book called ‘Molecules that Amaze Us’ [7]. 

We were originally concerned that people would not buy a book if a large part of its content was already freely available online, but we needn’t have worried.  It seems that the book has actually inspired readers to come back to the website, with hits increasing from 2,500 to nearly 10,000 per month in the year since the book was published.  (Okay, it’s not at the same level as a Youtube video of a piano-playing cat, but for a factual scientific site, that’s not bad).  So, it’s turned full circle – the website inspired the book, which inspired people to view the web site.  So far in 20 years the MOTM pages have had over 4 million hits, which is nearly 20,000 readers per MOTM article (which is far more than any of our Journal scientific papers could ever achieve).

So where will the MOTM project go in the next 10 years?  There are still plenty of interesting molecules to write about, and judging from the number of hits, the readership still seem keen to read about them.  The original goal of having the MOTM content written by numerous external contributors didn’t really pan out.  Nowadays, only about 2-3 MOTMs per year are written by volunteers, with the remainder being written alternately by the authors of this article.  We’d be keen on getting feedback from readers as to how to improve the site, or how to get more general engagement, particularly from authors (or volunteers to write a MOTM or two!).  Are there any new display technologies we should adopt (noting that most of the previous ones didn’t last long)?  Or should we forego the transient webpage format entirely, and stick to the tried-and-tested permanency of a book?


[1]. MOTM website at Bristol University -

[2] Teflon (MOTM June 2009) -

[3]. Capsaicin (MOTM April 2001) -



[6]. Tetraethyl lead (MOTM January 2001) -

[7]. P.W. May & S.A. Cotton, Molecules that Amaze Us (2014, Taylor and Francis, New York)

12/07/15 to 12/09/15


Tom O'Haver's picture

Congratulations of a great website. What I especially like about your site is the continuously-growing newest-first chronological order, similar to many blogs. It preserves the sense of history and and development over time, and you always know what's the newest stuff. My websites are usually of the continuously-edited document type, in which the overall organization remains the same but the content is gradually expended over time and new sections occasionally added. The problem with that is that you don't know what's new and different from the previous version.
Incidentally, there were a few chemistry-related sites that predated 1996, including the second CCCE online conference in 1995 (CHEMCONF, as it was called in those days): and a few other academic sites that are no longer being updated. One that is still going is "Introduction to Signal Processing in Chemical Analysis" (1995) , which is still in operation under a slightly different URL and name:

Tom O'Haver, Naples, FL

Paul May's picture

Hi Tom,

Thanks for the nice comments. You're correct about some sites predating the MOTM site. These were mostly in the US where the web took off a year or two before it did in the UK. Back in 1996 there were quite a few UK university chemistry departments that didn't even have an official website. I remember quite clearly trying to persuade my Head of Dept at the time that the single page of text that constituted the Bristol Chemistry home page simply wasn't good enough. What finally convinced him of the power of the web was when I showed the hit-counter which proved that the MOTM site was receiving 10x as many hits per day as the official Chemistry home page!

Bob Belford's picture

Hi Paul and Simon,

Thank you ever so much for contributing such an interesting article. Now, if I understand you right, your site (MOTM) had a huge drop in hits around the time Wikipedia came online, and then you recovered these by adapting the Q&A (Question and Answer) format. I know there are a lot of people on this list who create online educational material, including textbooks, and I have a question for you, and them.

Is anyone creating a textbook in this format? I remember Harry Pence's article on Browsers and Burrowers, and how the internet may change the style with how youth interact with printed material, and maybe a textbook written in the format you have developed would reach more students than the normal format. Is there a Q&A format textbook out there? In Chemistry? In any domain?


Paul May's picture

Hi Bob,

Funny you should mention that :-) After the success of the Q&A format for the MOTM pages, we decided to turn many of the web pages into a book, which came out last year. It's called 'Molecules that Amaze Us', and is meant for general interest science reading. The articles are based on the MOTM entries that Simon and I have written (plus a few new ones written specifically for the book), again written in the Q&A style, but without so much of the heavy chemistry (i.e. no mechanisms or too complex chemical equations), although we always show the molecular structure of the molecule in question. So far the book has been getting very favourable reviews, especially from teachers and science educators, but also from 'laypeople' who wouldn't normally think of reading a book about chemistry.
But as for 'proper' textbooks using the Q&A style, I don't know of any. Maybe as the factual content increases and the jokey anecdotes reduce it becomes harder to keep up the Q&A format?

Bob Belford's picture

OK, I have a confession to make. I am one of those reviewers, and after reading your book, I thought a Newsletter article would be great, (which is why I contacted you after the newsletter started). Here is my review,

But there is something deep here. There is a very real possibility that the youth of today read differently than the youth before the "Google Age", and I could be totally wrong, but they may not "deep dive" into an article in their quest for information, but "browse" through many. If their minds are getting "wired" to that form of functioning, than a browsable Question and Answer textbook may better fit their information needs then the textbooks we learned from.


Hi Bob,

The "Google Age" "browse" approach has come up before, but I certainly hope that it's not true that the youth of today need to get all of their information that way. It seems to me that the hit-and-miss, fragmented knowledge that would come from that approach would be far inferior to learning that comes from reading or hearing a logical, stepwise description of each topic. Am I just old?

I think that the "browse" approach is fine for supplementing our knowledge in an area where a fundamental understanding of the discipline has already been developed, but for a textbook that is designed to build the fundamental understanding, I think we should discourage the "browse" approach. I'm not sure that the question approach encourages browsing, but if it does, I'm agin' it.

Are you suggesting that a modern reader might not read all of a MOTM article, but instead would browse it, reading only portions of it? It seems to me that the MOTM articles have the logical, stepwise buildup of each topic, and that a reader would get a lot more out of each article if it's read straight through as opposed to a disjointed hit-or-miss approach. I like the question approach because it draws the reader in and encourages them to keep reading.

If the youth of today are drawn to what I think you mean by the "browse" approach, I wonder if it's the job of the old educators of the world to discourage them from using it.

Paul May's picture

Hi Mark,

I think it depends who the intended audience is, and what the aims of the book/article are. If the reader is a dedicated science student who wishes to get a deep understanding of a subject, then the only real way to do this (IMO) is via the traditional methods and textbooks, going through all the details meticulously and laboriously over a long period of time. For teaching serious science students, I don't think there's an alternative. But this way can be dull, time-consuming and only for 'science-geeks'.

However, there is a *huge* audience of laypeople (non science geeks) out there who have a frighteningly small knowledge of even basic science. Nevertheless, they are still curious about science, but would never dream of reading a normal textbook. They want to be entertained while they are being educated, i.e. they want Jackie Collins not War & Peace! So a 'browsing' style science book with (very) short chapters that they could flip back and forth in might be ideal for this type of reader. The MOTM articles are sort of halfway there. They are still linear (start at the top and follow the 'discussion' through to the end), but each topic is only a few pages long, and not too heavy going.

Hi Mark
One thing I've tried to address with the last two books in which I've been involved is getting interesting stuff over to the student audience around the school/college-university divide. I think as teachers we will all have encountered the problem of recommending accessible books to students. For years I could not get much beyond Atkins' Molecules or John Emsley's 'Molecules at An Exhibition'. There's not much more than that now, in contrast to the piles of books on astronomy or genetics (for example) that litter the 'Popular Science' section of bookshops. Yet chemistry is more important to peoples' everyday lives, if they did but know it, and we as educators have to try to find ways of doing this.

Tom O'Haver's picture

Carl Snyder's "The Extraordinary Chemistry of Ordinary Things" was also in that vein. But you are right, there's far too little of that kind of pop-chemistry, compared to the heaps of stuff for other sciences. And I would make the case that chemistry is more important in people's daily lives that astronomy, for example.

Funny you should mention Snyder's book, Tom. Back in 1994-6 I had a two year period when I was doing short-term contract jobs. I'd not recommend it, but it gave me the chance to think about getting chemistry across to students and others, and also to do a lot of reading. I looked at quite a lot of American textbooks, one of which was Snyder's 'The Extraordinary Chemistry of Ordinary Things'. It gave me ideas for new topics to put over and was one of the inspiration for Soundbites. I wrote about this apotheosis in an article ('Image Breakers') that appeared in Education in Chemistry in 1996. It does not seem to be available online, so Robert has kindly uploaded it to the main page of this discussion.

Tom, you may be interested in the books similar to Atkins and Emsley I now suggest to students. Modesty prohibits me from naming two :¬ ) but others are P. Le Couteur and J. Burreson, Napoleon's Buttons: How 17 Molecules Changed History, Tarcher, 2003 (of course); R. L. Myers, The 100 Most Important Chemical Compounds: A Reference Guide, Greenwood Press, 2007; Brigitte Proust, Petite géométrie des parfums, Paris, Seuil, 2006. (• if you speak French); R. J. Giguere (ed), Molecules That Matter, Chemical Heritage Foundation, 2008; M. Miodownik, Stuff Matters: Exploring the Marvelous Materials That Shape Our Man-Made World, Houghton Mifflin Harcourt, 2014; T. Gray, Molecules: The Elements and the Architecture of Everything, Black Dog, 2014; and A. Brunning, Why Does Asparagus Make Your Wee Smell?: And 57 Other Curious Food and Drink Questions, Orion, 2015. Readers may be able to suggest others, especially North American titles that may have escaped me.

Tom O'Haver's picture

Thanks for those great suggestions. I did read Napoleon's Buttons a few years ago and it was fascinating, but I didn't know about the others. It would be really interesting to teach a course (presumably for non-majors) using such books.

I don't know if it is a parallel to be followed, but one increasing trend in recent years is breaking down exam questions into sections; another is putting teaching material over in bullet pointed sections. Possibly chunking information in MOTMs is another example of this - the thought has only just occurred to me.

Hi all,

To respond to Bob's question, I don't know of any textbooks that use the "question format". Although I like the question format, it seems unlikely to me that it would make a big difference in whether or not folks would visit the MOTM site. I wonder if there's a broader explanation for why the MOTM site dropped off and then picked up again with the rise of Wikipedia. The bulk of information on Wikipedia has increased rapidly, so I wonder if initially, the wider exposure and short pages of Wikipedia led to a drop in MOTM hits, but after awhile, Wikipedia was seen as too detailed and just too much for many people. The shorter, cheerier, and conversational format of the MOTH, perhaps including the question format, was perhaps seen as more accessible.

I should add that I've been visiting and enjoying the MOTH site off and on for most of its 20 years, and I have often recommended it to students. I remember the time in the late 90s when I had a webpage on my class website that listed what I thought were essentially all of the good chemistry sites (including MOTM), and the list was not very long. Now this list would include a huge number of links.


Mark Bishop

I mentioned in my last post that I had a page of chemistry-related links on an old website. I was curious to see if the page still existed, and I was much surprised to discover that it's still out there in cyberspace. The fill name for the webpage suggests that I made it in 1998. Notice that the MOTM site is on the list. I haven't done anything on the website for well over a decade, so this page is history as much as chemistry.

On my current website, I don't even have a page of links, because there are just too many good sites out there.


Thanks for sharing your old site Mark. I note that the "Molecule of the Month" link works, but the "United States House of Representatives Committee on Science" link does not.

I wonder what that means?

Back in 1999-2000 there was not too much out there in the way of chemistry sites - certainly of use to teachers - and I spent quite a bit of time compiling one, which I circulated to a number of chemistry teachers. It was useful then, but there is so much out there now, I'd never think of doing it today.

Paul May's picture

Hi Mark,

Perhaps you're right. Wikipedia certainly has all the facts about any molecule you want to know about - but it's often presented in a dry textbook style. Where's the fun in that? On the MOTM site we've always tried to make chemistry fun and interesting, often with cartoons, interesting anecdotes, bad puns(!), etc. You don't get these with Wikipedia.

Tom O'Haver's picture

What fraction of the hits on MOTM are from Google or other search engines, rather than from direct links?

Paul May's picture

Hi Tom,

I'll try to find out from the logs, but I think it's actually quite a high percentage, maybe 50% or more, especially for the older pages. Some of those have been online with the same URL for nearly 20 years, and have been cross-referenced many times since, and that's one of the criteria the Google search engine uses to rank hits.

Tom O'Haver's picture

If a lot of the MOTM hits come from search engines, then an important factor would be the ranking criteria of that search engine, since most people look only a the first few hits in the search results. Wikipedia ranks very well in Google's PageRank because so many people cite Wikipedia articles in their writing.

SDWoodgate's picture

I think that a whole textbook in a question and answer format would be a bit wearing, BUT I do think that this style has merit. My website mixes information and interactive questions, where the information is on pages that occupy roughly a screen. I have sometimes used the question and answer format on the information pages. I would like to thank you for reminding me of the possibility to do this because I probably should use it more because it can be more engaging. I think that it is really important to recognise that the web is a different medium to which our principles of textbook authoring may or may not apply.

One comment that I would like to make about the Molecule of the Month web site (which I do (and have for years) think is very good) is that when I went there in the context of this paper, it took me longer than it should have to figure out what I was meant to click to get the page of information about the molecule. One thing that I am continually astounded by in my own work are comments from students who claim they didn't know what to do - namely they need instructions. H and JS is a bit cryptic - I now realise that the dropdown is actually a set of bookmarks - that wasn't clear either. There also could be a wee note about the JS version taking longer to load. Food for thought!!

I have been following this discussion (thanks) and my attention was caught by the recent comment about providing students information in smaller bits, i.e.,

"...I don't know if it is a parallel to be followed, but one increasing trend in
recent years is breaking down exam questions into sections...."

I do agree that student attention spans and reading comprehension skills appear to be different than when I started teaching 35+ years ago. Partly in response to this and to some changes in standardized testing techniques, I have been using for some time exam questions that involve "reading passages," usually posing a problem in a larger context than simply being a plug-and-chug type.

With respect to the assessment side, however, I have found it very useful to break down the problem into some defined smaller key questions that build up to the final step of a solution. This has greatly helped me assess the point at which students falter in their understanding of the problem-solving task AND it also helps me assess how well (or not) the students can connect-the-dots between the individual steps.

It can be quite illuminating (and disheartening) to discover that students cannot answer a significant problem that I believe they are well prepared to solve only because they fail to understand the basic issues that the problem solving rests upon. I have learned that students are quite good at learning how to solve problems that follow a more or less standard algorithm, but easily become flummoxed when a slight twist is introduced.

So rather than seeing this as a sign to lament, "chunking" the harder questions has helped me and the students receiving the graded papers discern where the learning falters and needs to be addressed.


Especially since modularisation of British A level (immediate pre-University) exams, exam questions have been broken into short sections, where once upon a time they consisted of a paragraph of text with just one long answer expected. This enables students to concentrate on one thing at a time (as I say to students, helps the blokes as men can only do one thing at a time :¬) ).

Good point, 'the web is a different medium'. I tend to use it as somewhere to dip into to get answers, rather like looking up something via the index of a book, so it is no surprise that students may think that way.

Paul May's picture

Thanks for the comments. Maybe I should add buttons that say 'Click here for HTML page' to make it more obvious.
I've only started converting some of the more recent MOTMs to JSmol this week, and didn't realise they take a while to load. I'll add a warning about the load times.