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Science blog

My New (Old) Spectrometer

Having dabbled endlessly with home-made spectroscopes (which display a spectrum but frustratingly allow no measurements), I kind of struck lucky on eBay with a Bunsen-Kirchoff style spectrometer. ‘Spectrogoniometer’ would perhaps be a more apt name for this type of instrument as it allows measurement of the wavelengths of individual lines of a spectrum through the […]


The way we were: Slugs!

Perhaps the most bizarre unit of mass ever must be the ‘Slug’. Acc Wikipedia: The slug is a unit of mass associated with Imperial units. It is a mass that accelerates by 1 ft/s2 when a force of one pound-force (lbF) is exerted on it. Imperial Science Quiz question: how many BTUs are needed to […]


How to be a Sceptic (Carl Sagan)

From his book The Demon-Haunted World: Science as a Candle in the Dark (1995, from page 197-198) (courtesy of ‘Nicodem’ of What sceptical thinking boils down to is the means to construct, and to understand, a reasoned argument and, especially important, to recognize a fallacious or fraudulent argument. The question is not whether we […]


Memory lane: First Preparation of Plutonium Metal

I’m reading Glenn T. Seaborg’s seminal ‘The Trans-uranium Elements’, which is one third fascinating chronicle of the discovery of… well, the trans-uranium elements, one third textbook on the chemistry of these elements and one third of the same but on their nuclear properties. It contains milestone after milestone for this extremely prolific research team that […]


Spinning Bullet on Ice

Just saw this in a repeat of ‘You have been warned’. A 9 mm calibre bullet is fired at thick ice. Rifling causes all modern fire arms projectiles to have both linear and angular momentum because the rifling causes to bullet to spin (very fast) around its own axis, improving stability during flight. When the […]


Gallium Dissolving in HCl…

Here something else you don’t see everyday; liquid globules of Gallium metal dissolving in hydrochloric acid: Gallium has a melting point of just under 30 C, so that tells us this dissolution was done above that temperature or that reaction heat caused the metal to melt! According to the owner of the photo it took […]


Ferric Ammonium Alum Preparation: an Alkaline Route

I’ve prepared ferric ammonium alum (NH4Fe(SO4)2.12H2O – CAS 10138-04-2) many times, usually with useful product to show for but rarely without problems. Very variable yield, unexpected precipitates, incomplete oxidation, excessive foaming (with HNO3 as oxidant) are all problems I’ve encountered. And once I attempted one madcap scheme to try and synthesize this alum which involved […]


When an anti-science environmentalist became pro-science (and pro-GM foods)

As always I’m the last to get the memo. So this passed me by, by quite a bit, but it remains as relevant as when it was first published. Mark Lynas is a (in)famous former anti-GMO campaigner and co-coiner of the ridiculous ‘Frankenstein foods’ term who at some point decided to actually sit down and […]


Indigo Chemistry – Dyeing with Woad

Watching a repeat of Tony Robinson’s ‘Worst Jobs in History’ last night reminded me of some interesting plant chemistry that’s been exploited since Roman times: the extraction of indigo from Woad (Isatis Tinctoria). Woad dyers in Elizabethan times were essentially banned from towns and cities because the process of producing the beautiful blue dye from […]


Clap Your Hands if You Believe in Science

By Julie Walsh Recent research into the properties of fluids at the microscale level has managed to present this topic in a manner that might appeal to anyone who shares a scientist’s curiosity about the world, regardless of how far they have progressed in their education in chemistry or physics. When we manage to combine […]