The non-scientists among us will wonder why some elements on the Chemistry Clock have the same colour, and why the numbers of the elements do not match the actual time...

The answer is relatively simple: For the colours, elements in the periodic table are divided into different groups. There are, for example, alkaline Earth metals such as beryllium, magnesium and calcium (light green on the clock), and noble gases such as neon, helium and argon (purple). Then head over to this website

So in what way are the elements arranged? Scientist will already know, otherwise one word should suffice: atomic number. That's the number of protons found in the nucleus of an atom. So only clever people can look at this clock :).

And this is what causes people with little knowledge of the periodic table to cast wild theories about how the clock works. The rest of you, though, will probably get what time it is when we say that at Oxygen: Phosphorus O'Clock, many TVs are turned on to find out the day's events.

Do you have a Fluorine-to-Chlorine job? Being as clever as you are, you probably took no time at all to work that one out, right?

Want a really original clock for your room or workplace? One that no periodically-challenged non-geek can understand (at least until you explain it to them!)? Then the Periodic Table Wall Clock should be just the ticket for you!