Some of you might remember about a month ago that we recorded a video with this one!
It’s Caesium; it’s the emperor of the alkali metals but you know we’ve been looking the ...
YouTube feed back and we’ve been really astonished through
the number of people, that are ,one, interested in the Science and two, really want
to egg us on to something a little bit mad.
So, unfortunately, I’m not going to put this into water today, because it’s far too expensive!
but what I did do was, me and Neil had a look at the chemical’s purchasing database of the university.
and we spent about 60 pounds of our own harden earned money to buy small sample of Caesium, which,
yes, you guessed it, we’re going to throw into water today!
Many people get quite excited about Caesium, because they’ve seen a very famous video which
predates YouTube, but I think now, it’s seen many places in which someone drops of a tiny piece of Caesium
into water and it explodes enough to break the vessel that the Caesium is in.
So, some of you’ve noticed, the stoic Neil Barnes our senior technician on the project
and he’s been really really busy, last Friday, he designed and built a specific piece of apparatus,
to liberate the Caesium from its glass surrounding or its phial.
You pull the string then you let it go!
Some of you might have heard of this Large Hadron Collider that they’ve got
in Switzerland in CERN. This is actually a small metallic collider,
that we’re going to use to liberate Caesium and study some of its Chemistry.
And the reason, that Caesium is so reactive, is that, the atoms of Caesium, are very large,
much larger than Rubidium, Sodium and Potassium, and so, the reaction with water, which removes
an electron from the Caesium atom, is much easier because it needs less energy.
So, if there's less energy needed to remove the electron from the Caesium,
than there is more energy left, to release as heat.
So, we're behind the boiler shed which is out the back of the department
simply because it allows us to control the environment a little bit more.
So, back by popular demand, Caesium mark two, we have a gram of Caesium,
in a glass phial, we have a remote control device, let’s see,
what happens when we put it into water?! We’ve actually got some students watching,
I don’t know perhaps they rig their original experiment to explode the thing, 00:02:46.80,00:02:46.760 but this has become a classic! And I think,
many of our viewers expect us to have a bigger and better explosion than they did!
So, here is the Caesium, see in the bottom of little tube and now e're gonna actuate
this small metallic collider to initiate the reaction.
So, time for the safety and let’s see what happens! Ready guys?!
I’ve never seen Caesium react with water, and it might be quite exciting!
Well you can see it was a very vigorous reaction, and the whole of the gram of Caesium
reacted instantaneously, the moment it hit the water.
Nice, purple flair, really quite nice Chemistry!
. . . . . . . . . . . . Captions by www.SubPLY.com