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Nickel is element number 28 between Cobalt (27) and Copper (29)
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Nickel has been known for a long time as an element or as a mixture with other metals
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But it was only isolated as an element in
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1751 by Axel Friedrich Cronstedt in Sweden.
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To begin with it didn't have really much use and the big breakthrough for Nickel came in the 19th century
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when it was discovered that if you added Nickel to Steel
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you could make very strong armor.
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Particularly armor plates for ships so that
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your ship was stronger than the enemies and their shells couldn't penetrate
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About the same time, a large deposit of Nickel or Nickel ore
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was discovered in Sudbury in Ontario in Canada so that in some ways...
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Nickel has become a Canadian element.
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There are also now large deposits in Russia
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But the Canadians have become so proud of Nickel
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Axel Friedrich Cronstedt, his portrait is on the premier medal of the Canadian Institute of Chemistry
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It is thought that the nickel deposit in Canada probably came with a meteorite from outer space,
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because meteorites quite often have a very high Nickel content
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and presumably in the very distant past a massive meteorite struck what is now Canada
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and buried itself in the Sudbury region.
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You don't need a very large diameter meteorite to contain an awful lot of metal.
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The big breakthrough in the refining of Nickel came in 1890
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when the British chemist, Ludwig Mond, who was a major industrialist, had a problem in his chemical works
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that some of the Nickel valves on his chemical plant were found to corrode - dissolve
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And he discovered or his assistant Finker discovered
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that this was caused by a reaction between Carbon Monoxide and Nickel.
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In 1890 they published a key paper about the compound.
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The compound is called Nickel Tetracarbonyl { Ni(Co)4 }
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It consists of essential nickel atom surrounded by four Carbon Monoxide groups arranged in a tetrahedron.
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What made this compound really unusual is that when you think about transition metals - Iron, Copper, Nickel,
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you think of coloured salts which are solids all the time
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Nickel Carbonyl was a liquid, it was colorless and it boils at 43° C (107.6° F)
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So it was almost a gas at room temperature.
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The important thing about Nickel carbonyl
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is that you can distill it easily and if you heat it up it decomposes back into nickel and carbon monoxide
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So it turned out to be a really good way of purifying Nickel ore
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And Mond set up a company specifically to get nickel from the ores in Sudbury.
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So he was reacting the ore with carbon monoxide which extracted out the nickel and in fact some of the iron -
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both of these so-called carbonyl compounds
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You can then separate them by distillation
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Heat them up to decompose them and you get absolutely pure nickel and some iron as well.
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It was then discovered that nickel was a very good catalyst for reacting organic compounds with hydrogen
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And particularly it was discovered that you could hydrogenate vegetable oils, sort of cooking oils that you use.
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And these oils have Carbon-Carbon double bonds.
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If you react this with hydrogen, the melting point of the oils increases
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so the material becomes more like butter
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And this is how you make margarine, by reacting vegetable oil with hydrogen and the Nickel is the Catalyst.
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The hydrogen is absorbed onto the surface of Nickel the organic compound is also absorbed onto the surface
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and when the molecules are held there, the hydrogen can transfer from the nickel onto the carbon of the double bond.
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[Music]
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I was very keen to do a big experiment demonstration in this video,
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and I wanted to do it with a material called Raney Nickel.
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Murray Raney was an American chemist working on the hydrogenation of fats trying to make a better catalyst
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and the problem with the catalyst is, because it is solid and the molecules are absorbing on the surface
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the bigger the surface area within reason, the better the catalyst.
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So he needed some way of dividing up the nickel
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so it was in very small particles, so it had a very large surface area
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And he hit on the idea of mixing molten aluminium and molten nickel - these melted metals
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And they mix when they are liquid, but when they solidify they separate
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So you end up with a lump of aluminium with tiny bits of Nickel embedded in the solid
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rather like currants or cherries in the cake
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[Neil opens the can]
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You can then put these mixed nickel aluminum pellets into sodium hydroxide
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[Music + experiment sounds]
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The sodium hydroxide dissolves the aluminium,
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rather like we've done before with Coke cans
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and they leave the nickel quite untouched
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But they come out like removing the cherries from the cake
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and they have a very low surface area.
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So now my experiment.
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I had read that Raney nickel is Pyrophoric, it reacts with oxygen in the air and bursts into flames
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So I went to talk to my colleagues in organic chemistry who use Raney nickel
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and you buy it as a slurry so it's wet to avoid it bursting into flames.
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So I got a bottle which looked a bit old, but I was assured was probably okay
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And I persuaded Neil to pour it onto a filter paper
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And so what I expected was that it would dry out
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and then you would be left with this dried tiny particles of Nickel which would
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absorb oxygen, start burning, heat up more and more and burst into spectacular flames
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Unfortunately, it didn't. In fact when Neil eventually set fire to the filter paper...
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and the nickel didn't seem to burn
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Clearly we had a dud batch
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I think that the air had got in and slowly dissolved in the water and reacted over a period of months
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and oxidized the nickel so probably what we had was some form of nickel oxide
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But they are all fairly black in color so you can't really tell what you've got
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So I rushed off and found another professor who had a much fresher sample
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and he came down with his sample
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and he told us we had to dry it on the hot plate
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and he got quite worried, thought we'd used rather a lot of nickel.
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We heated it up, we had all the cameras
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the GoPro, the thermal camera, Brady standing there
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so excited, and eventually...
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it glowed slightly...
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And what this demonstrates, is that sometimes
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what chemists tell you about reactions are not always what happens in the lab.
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However you've got to imagine
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that if you're making margarine on a huge scale...
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Tens of thousands of tons, and have got a huge amount of Raney nickel
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then probably you can get quite a serious fire.
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But we don't have that much Raney nickel, and we don't want a serious fire.
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So, well, first of all let's look at some nickel
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Neil has produced some Nickel pellets
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So these are just labelled as general-purpose nickel
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They're lumps of nickel. Quite a few chemists like to use Nickel spatulas
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because they are more resistant to strong acids than stainless steel ones.
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You can have over here...
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This is quite nice. This is a...
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Gauze that is made of very fine Nickel wires.
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I think this one is designed for Electrochemistry so you can get a very high surface area.
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Nickel has also been used quite often for electroplating in the days when cars had shiny bumpers
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I can't remember what Americans called bumpers...
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Fenders!
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And these consisted of steel, which were plated with nickel and on top of the nickel, was chromium.
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So the Chromium gave a nice shiny look but the Nickel bonded them together
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Nickel has very colorful salts.
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and our undergraduates, in their first year do a very nice experiment
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where they take Nickel Chloride { NiCl4 } that is green
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And they react this with ammonia, so that each nickel atom is surrounded by six ammonia atoms.
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The Nickel ammonia complex { [Ni(Nh3)6]2+ } is a nice purple color
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They then have to do a separate experiment to measure how much nickel is in the sample
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to see if they made it properly.
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They do this by dissolving up their nice purple compound
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adding an organic compound called dimethyl glyoxime
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which binds to the nickel and forms an insoluble red precipitate
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which they filter off and weigh, so they can see how much nickel there is in their compound.
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So in a single experiment...
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they have gone from green to purple to red.
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We're not showing you the experiment because then our students might cheat!!
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So you'll have to come as a student to do it yourself
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Then Neil thought about it.
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He realized that as the water was evaporating and the individual particles of nickel got dry
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each of them oxidized so you never had the whole mass going off at once
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So what he decided
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was to put the wet Raney nickel in a vacuum desiccator
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This is a vessel which you can pump out all the air
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And you're pumping on it of course the water also evaporates but the nickel is dried in a vacuum
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so there's no oxygen for it to react with
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So when he opened the tap, the air, containing the oxygen rushed in...
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And all the nickel reacted at the same time and produced quite a satisfying whoosh
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[Brady:] We've made videos about every element on the periodic table.
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If you'd like to watch them in order, I'll put a link on the screen and in the video description
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There's a playlist of them all one to 118. Might take you a little while...
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We're constantly updating these videos with new ones like the nickel video you just watched.
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And in fact we've filmed so much about Nickel there's some leftovers.
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If you'd like to watch them, I'm also linking to the extra footage.
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You can go and check out even more details the professor had to share.