On 15/08/2012 21:40, Andrew Gabriel wrote:
In article m,
newshound writes:
Scary. Anyone who did A level chemistry forty or fifty years ago would
have been very well aware of the risks. Now you have to have safety
screens when the teacher is using dilute acids. Somewhere along the way
we lost the science.

I'm told practicals are a thing of the past in most schools,
not due to H&S, but due to no time left after covering everything
that's centrally mandated nowadays.

However, it reminds me of a lecture at university, Materials Science
topic. Lecturer started with a balloon (blown up) in one hand, and
a pin in the other, and jokingly said
"I should really have a safety screen for this!"
When he stuck the pin in the balloon and it burst, the knot shot off
and got me in the eye, which was quite painful.

;-)

I am sure we did plenty of things at school that were dodgy then - let
alone now...

Making Nitrogen Triiodide was fun (we were allowed to make it on the
understanding none of it left the lab... not sure is there were any of
us that did not spirit at least some out!)

A demo of converting copper coins into "silver" by rubbing with Millon's
Solution (a Mercury and Nitric acid reagent IIRC) - apparently this was
a technique that kept the teacher in question in cheap beer at a local
pub through his university days, due to the peculiarities of pre decimal
coinage.

The manufacture of bromide gas was also entertaining when someone forgot
to hook the reaction vessel up to the gas jar and filled the lab instead ;-)

And chucking various reactive metals in water was always fun.


--
Cheers,

John.

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