Thursday, January 29, 2009

"All television is children's television." - Richard P. Adler

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On something we watched in Secondary School:


Brainiac: Science Abuse - Alkali metal experiment with forged results

"One experiment conducted by Brainiac aimed to illustrate periodic trends in the alkali metal series. It showed the violent reactions of metallic sodium and potassium with water, in which the hydrogen produced subsequent explosions, and intended to demonstrate the even greater reactivity of rubidium and caesium by dropping them into a water-filled bathtub. However, the reaction was not particularly spectacular, and the crew substituted explosives for the alkali metals. This is clearly visible in the footage, in which an "explosives" sign can be seen on the premises, and an exploding cloud of hydrogen gas, which one would expect in an alkali metal reaction with water, was not visible.

The Brainiac staff have admitted that the explosions had been faked. According to Tom Pringle, Brainiac's "Dr Bunhead", very little occurred in the real reaction of caesium and water, as the large volume of water over it drowned out the thermal shock wave that should have shattered the bathtub. The crew decided to set up a bomb in the tub and use that footage to generate the explosion.

Similar experiments with caesium or rubidium have been repeated; these include Popular Science columnist Theodore Gray's experiments with the alkali metals, the "Viewer Special Threequel" episode of MythBusters, and an attempt made as part of the Periodic Table of Videos series created by several faculty members at the University of Nottingham. In no case were the rubidium and caesium reactions extremely violent, much less quite as explosive as the Brainiac episode depicted."


Damn, so much for that Caesium Bomb idea!
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