so this is an experiment that I haven't
tried for about 30 years and I lasted
for my children in that living room so I
don't know if it'll work still but let's
see
it's a reaction of copper chloride with
a cupcake holder which is in fact just
aluminium first of all I'm going to
dissolve some up and make a fairly
concentrated solution so but it makes
rather a nice green solution in fact
perhaps will make the solution up in
here it's easier to stir you can see
it's a long time since I've done such
things so we're making up a concentrated
solution of copper chloride it's now
mostly dissolved and it's a really very
pretty color I'm good to place this here
and so imagine I'm doing this on the
floor of our living room which has a
carpet on it and the cupcake holder was
on the carpet so I poured this in and
as you can see here nothing much happens
to begin with but then if you watch it
starts boiling really quite nicely you
can see the nice precipitate of copper
where we can take it out and you can see
there now imagine I was doing this for
my children who were quite small at that
time and whoosh the stuff went through
the cupcake holder and onto the carpet
and through the carpets and my wife was
not at all pleased because they're in
the middle of our carpet was a hole we
now have a new carpet so the first time
it went through quite quickly so this
time we're going to do a double we have
two aluminium cupcake holders here and a
strong solution of copper chloride and
we pour it in here now watch see if
anything happens
the reactions a bit slow to start
because the aluminium has an oxide layer
but now it's got going and you can see
it's begun boiling got really quite
excited and it's now gone through both
layers and you can see there's rather a
nice color of the copper the metallic
copper and what has happened is the
aluminium has reacted with the copper to
make aluminium chloride and copper metal
it feels really quite warm even through
here so the chemistry is that the
aluminium is reacting with the copper
chloride to make metallic copper which
is what you can see there and an
aluminium salt now the message of this
is that even something like copper
chloride which sounds a fairly innocuous
material can be pretty reactive if you
put it in the presence of the right
material in this case aluminium
so chemists should always be careful
when designing a reaction in the
container to make sure that they don't
get an unexpected reaction and if I'd
thought about that we would have saved
money for a whole carpet