SCI Bristol & South
West Regional Group started their 2003-04 Lecture Meetings with Elements
of Surprise by Dr John Emsley
A meeting report by Raymond
Holland Chairman SCI Bristol & South West Regional Group
Thursday, 23 October 2003
John Emsley is a chemist, an authority on phosphorous chemistry,
who became the Science Writer in Residence at Imperial College
and then Cambridge University. He wrote for a number of years
'The Molecule of the Month' column for The Independent, bringing
home to a wide readership how chemistry impinges on every
aspect of our daily lives.
 His
talk, 'Elements of Surprise', which attracted a large audience
of 65, including many young people, started with a musical
introduction 'The Elements' written and sung by Tom Lehrer
to the tune of the song 'I am the Very Model of a Modern Major
General' from Gilbert and Sullivan's operetta The Pirates
of Penzance.
His talk revealed that most elements have roles in history,
or uses in modern life that are quite unexpected. He started
with aluminium, a very expensive metal until 1886, when a
method was found to produce it, very much more cheaply, electrolytically.
Then he moved on to americium, which is used in smoke detectors.
He listed 25 elements essential to human life, highlighting
oxygen, carbon, hydrogen and his favourite element phosphorus,
which is used in medicine, matches and firebombs. Selenium,
is an essential trace element but overdosing can produce foul
breath and body odour and in excess death! Without selenium
sperm cannot swim! He recommended men to eat more liver and
steak & kidney, both high in selenium. Another trace element
is Nickel found in baked beans and tea. Nickel aluminide is
stronger than steel and gets stronger when it gets hotter.
Nitinol, (55% nickel, 45% titanium) is used to make unbreakable
spectacle frames. Nickel CDs will hold data for around 1000
years. Whether anyone will have a CD player in 3003 was debatable!
The discovery of oxygen is usually attributed to Priestley,
Scheele and Lavoisier in the 18th century but in 1624, the
first ever submarine was demonstrated to King James the first.
It travelled under water for two hours and the air was 'refreshed'
from a container. Was this oxygen from gently heated saltpetre?
Today, emergency oxygen for aircraft passengers is not stored
in heavy cylinders but is made instantly from sodium chlorate
and iron filings.
He completed his A to Z tour of Surprise Elements with zirconium,
its most dramatic use is in ultra strong ceramics, stronger
and sharper than toughened steel. Often found in golf irons.
John Emsley ended his informative and entertaining talk by
saying that he was proud to be a chemist and that all chemists
have a duty to communicate. He certainly is a great communicator!
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