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unionised
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Perfectly practical.
I used HCl a week or so ago to strip the nickel plating from some brass.
It works a lot better if the acid is warm.
Do you know how galvanising works?
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Texium
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Well, if it's just a thin plating it's a lot more practical than a heavier gauge coating or a larger piece. For me, it took about four hours for a
fairly thick nickel plating to completely react with slightly above room temperature conc. HCl.
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blogfast25
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Quote: Originally posted by unionised  | Perfectly practical.
I used HCl a week or so ago to strip the nickel plating from some brass.
It works a lot better if the acid is warm.
Do you know how galvanising works? |
Aren't you kind of making my case for me? A week??
Galvanisation doesn't explain why these nickel coatings didn't dissolve. Nor why some electro plated silver nickel spoons of mine didn't dissolve in
H2SO4 after I had nitric stripped off the silver.
Nickel does dissolve in HCl and H2SO4 but it is very slow.
[Edited on 28-4-2014 by blogfast25]
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Zyklon-A
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| Quote: Originally posted by unionised | Perfectly practical.
I used HCl a week or so ago to strip the nickel plating from some brass.
It works a lot better if the acid is warm.
Do you know how galvanising works? |
Do you know how galvanizing works?
That isn't galvanizing, that's just nickel plating.
Galvanizing, is completely different:http://www.example.com
[Edited on 28-4-2014 by Zyklonb]
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unionised
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"Aren't you kind of making my case for me? A week?? "
If I had done it ten years ago would that have made it slower somehow?
I didn't say that it took a week.
And yes, I do know how galvanising works.
Specifically, it's using zinc plating to stop the corrosion of steel.
It works because the more reactive zinc dissolves first.
Now consider the nickel plating on a NIB magnet.
It's in the same position as the iron in galvanised iron.
It's in electrical contact with a more reactive metal- so it will dissolve slowly (if at all).
Did you not realise that the galvanisation analogy is why the Ni coating on magnets survives?
Happy now?
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blogfast25
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Sorry, I misread you on the 'week'.
I know what you're referring to with the galvanisation analogy. But that's not what happens here. When the NdFe filling has been fully consumed, the
Ni still didn't dissolve. Well, very slowly of course. Same with the silver coated nickel spoons: even when the silver is removed reaction with H2SO4
is really slow.
[Edited on 28-4-2014 by blogfast25]
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unionised
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Incidentally, "nickel" spoons are likely to be this stuff
http://en.wikipedia.org/wiki/Nickel_silver
which is largely copper - so you wouldn't expect it to be attacked by HCl and only slowly by H2SO4.
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blogfast25
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That I'm certainly willing to investigate, having plenty more of these spoons, marked EPNS...
[Edited on 28-4-2014 by blogfast25]
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unionised
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Electro
Plated
Nickel
Silver
isn't going to dissolve well without an oxidant.
So, the reason you think nickel doesn't dissolve is that you were actually mainly using copper when you did the experiment.
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HgDinis25
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I haven't seen any spoons with that alloy. Quite interesting.
Anyway, knowing what one is using in a chemical reaction is a MUST. Always research about what metals might be present in the items you use,
blogfast25. And if you have any doubts on it, you can always use the Beginnings forum to help you out.
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LanthanumK
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I tried to extract metals from a nicad battery. Never got anything but a mess.
hibernating...
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cyanureeves
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a million years ago i took parts to a galvanizing plant and i saw them dunking huge skids platforms into a gigantic tank with steaming hot zinc.
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blogfast25
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| Quote: Originally posted by unionised | | So, the reason you think nickel doesn't dissolve is that you were actually mainly using copper when you did the experiment. |
I think I should test that first before we posit this as certainty.
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unionised
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Good point.
Are they magnetic?
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blogfast25
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Haven't tested that yet.
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unionised
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Would it help if I sent you a magnet?
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blogfast25
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Neomagnets? Could I have a hundred, please? 
Jokes aside. I dissolved a few grams of EPNS spoon (silver coating and all) in a few ml of 70 % nitric and that gave a fairly dark blue solution
(indicative of Cu(II) nitrate). Diluted that with a bit of water and added excess of NH3 33 % and the copper tetrammine complex shows up with a
vengeance. These spoons contain plenty copper. The nickel hexammine complex is blue too but not as intense.
As luck would have it a hoarder like me had kept these nickel coatings from neomagnets and I've just dissolved some slivers in 70 % HNO3 too. That
solution is decidedly green. More tomorrow...
Edit:
A few more observations.
The spoons aren’t magnetic, the slivers of neomag coating are.
When treated with excess NH3 33 %, the neomagnet coating solution in nitric acid also turned a deep blue. I don’t remember the nickel hexamine
complex to be so intensely blue. Hard to distinguish with the naked eye from the corresponding Cu(II) tetrammine complex. But the original coating
solution in nitric acid was indisputably green.
Sanding down a bit of spoon (removing the silver plating) reveals something like a light coloured brass, indicative of a copper alloy.
I’m now subjecting a few slivers of neomagnet coating to 37 % HCl and comparative strength H2SO4. At RT so far very little reaction…
[Edited on 4-5-2014 by blogfast25]
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Eddygp
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According to the OP's observations, it may as well be metallic cadmium. Consider this possibility.
there may be bugs in gfind
[ˌɛdidʒiˈpiː] IPA pronunciation for my Username |
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Texium
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Well, it could be if cadmium was magnetic, but as cadmium isn't magnetic, it is much more likely that it is nickel. It can't possibly contain much
cadmium. It would have to be mostly nickel and/or iron to be magnetic.
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Eddygp
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Oh right, I thought that I had read that the metal obtained was diamagnetic. Sorry about that.
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PHILOU Zrealone
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Ni is magnetised by a magnet, just like iron; old (before Euro) coins of 50 belgian francs were 7.00 gr of nearly pure Nickel.
NiCl2 is green, but so does FeCl2...while CdCl2 is colourless...addition of NaOH will reveal precipitates of a granny smith green colour for Ni(OH)2,
about the same kind of colour for Fe(OH)2, but the later turns darker and darker when exposed to air due to Fe(OH)3 formation (brown-red)...and
Cd(OH)2 is white.
CdS is yellow while FeS and NiS are black.
Cd(2+) and Ni(2+) do form complexes with ammonia, Ni complex is deep blue, but less than the copper one.
I don't know the color of the Cd complex.
Ni(2+) forms a red-pink complex with dimethylglyoxime.
Ni(NO3)2 water solution forms a pink-violet explosive (when dry, confined and exposed to a flame) precipitate when mixing hydrazine hydrate solution
to it. At first precipitate might look blueish. (Ni(N2H4)3(NO3)2)
[Edited on 12-6-2014 by PHILOU Zrealone]
PH Z (PHILOU Zrealone)
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Brain&Force
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I have a sample of nickel metal shot at my school, but it's only VERY weakly magnetic. Only a neodymium magnet will pick the pieces up. Is nickel
supposed to be far less magnetic than cobalt and iron, or is there some other factor in play?
At the end of the day, simulating atoms doesn't beat working with the real things...
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DraconicAcid
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| Quote: Originally posted by PHILOU Zrealone |
Cd(2+) and Ni(2+) do form complexes with ammonia, Ni complex is deep blue, but less than the copper one.
I don't know the color of the Cd complex.
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Cadmium is like zinc- a d10 system, so practically all of its compounds and complexes are colourless (unless the anion/ligands are
coloured).
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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PHILOU Zrealone
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| Quote: Originally posted by DraconicAcid | | Quote: Originally posted by PHILOU Zrealone |
Cd(2+) and Ni(2+) do form complexes with ammonia, Ni complex is deep blue, but less than the copper one.
I don't know the color of the Cd complex.
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Cadmium is like zinc- a d10 system, so practically all of its compounds and complexes are colourless (unless the anion/ligands are
coloured). |
Thank you for that valuable information.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Texium
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| Quote: Originally posted by Brain&Force | | I have a sample of nickel metal shot at my school, but it's only VERY weakly magnetic. Only a neodymium magnet will pick the pieces up. Is nickel
supposed to be far less magnetic than cobalt and iron, or is there some other factor in play? |
Really? That's interesting. I have a 1938 Canadian nickel and it is quite impressively magnetic. Even a weak fridge magnet will pick it right up.
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