Rosie's Selection

Another five favourite elements list, this time from Periodic Table of Videos viewer Rosie Mitchell.

Love her little stories to go with each one... She sounds like she'd be a great PTOV presenter, doesn't she?

1. IRON



Rosie says: "I have a personal stake here. If my father's forebears hadn't moved up from Cornwall in the mid nineteenth-century to work the iron mines, and mingled with my mother's forebears down from Scotland for the same reason, I wouldn't exist. And that's without the whole existential arguments around the chemical and physical properties of iron being fundamental to the nature of the universe. And that it does all that funky magnetism stuff. And that Earth itself is just a big iron cannonball with some interesting deposits in a thin layer ion the surface. A real superstar amongst elements."

2. SCANDIUM



Rosie says: "Because scandium is the final proof, if proof were needed, that all elements are interesting. Suppose that there is such a thing in the periodic table as a boring element. Then there is a lightest boring element, and that makes it interesting. When I first encountered the periodic table at school I thought boron must be boring because it sounds like boring and we never did anything with it in the lab. So it was interesting to me and when we were invited to synthesise an element of our choice in the A-level lab I synthesised boron just for the hell of it. But as Debbie says, boron chemistry is far from boring so it's not sufficient proof. So, run the gamut of elemen scandium... Huh? Scandium really is dull, and so it's the first dull element. If I were a chemist, which I ain't, I'd do my PhD thesis on the chemistry of scandium."

3. THALLIUM



Rosie says: "I've heard it said - and this may be an urban myth - that a key piece of evidence against (murderer) Graham Young who put thallium salts in his colleagues' tea emerged when one of the investigating officers recognised the symptoms of thallium poisoning from an Agatha Christie novel he'd recently been reading. One up for the humanities then."

4. MERCURY



Rosie says: "Today's children are victims of common sense. Nothing would ever be achieved if, as the more populist pundits would have us believe, we relied on common sense. Madame Curie would no doubt have lived a long life if she hadn't played fast and loose with radium salts (allegedly her papers are considered too dangerous to handle) but she'd never have won two Nobel prizes. Children deprived of experiencing mercury in the school lab not only miss out on some of the funky tricks that can be done with this fascinating element (like the mercury motor) they miss out on pushing beads of spilt mercury around the bench. Mercury should be treated with great respect but there are many bead-pushers who have survived into old age."

5. PROMETHIUM



Rosie says: "The Frankenstein's Monster of the periodic table. Nobody with any curiosity can resist a gap so it was inevitable that scientists would try to fill those in the periodic table. Promethium turned out to be very nasty indeed, in contrast to the comparatively benevolent weak beta-emitter technetium. When it decays it fires off X-rays for heaven's sake! It's not even particularly useful. So, promethium is fascinating for its sheer malevolence."

Previous top five contributions have come from Ryan, Nurdrage, Sarah, Alex and I've also done a "five most viewed" list.

If you'd like to make a contribution, get in touch.