Sciencemadness Discussion Board

Sodium Hydroxide and Nickel

NEMO-Chemistry - 3-3-2018 at 13:35

A while back i asked about dissolving Nickel, I couldnt find the thread but my ropey memory said Woelen had suggested putting the shavings in sodium hydroxide and letting it evaporate.

So I have done this, BTW i got a new radiator in the lab :D so its warm and dry now.

Anyway i added some water until it just went to a liquid over the Nickel flakes. Its now pretty dry but has made large almost needle like crystals!! most if not all the Nickel is there and no colour change. But I have never seen sodium hydroxide prills go to a liquid then give large flake/needle like crystals!!

Any ideas? Oh and yeah i did look it up on wiki after and discovered it potassium hydroxide your supposed to use not sodium :D.

Boffis - 4-3-2018 at 01:45

Nickel will not dissolve in sodium hydroxide solution. In fact we use nickel crucibles for NaOH fusions.

NaOH solution absorbs carbon dioxide from the atmosphere fairly readily and the resulting sodium carbonate is very insoluble in strong NaOH solution.

NEMO-Chemistry - 4-3-2018 at 06:51

Quote: Originally posted by Boffis  
Nickel will not dissolve in sodium hydroxide solution. In fact we use nickel crucibles for NaOH fusions.

NaOH solution absorbs carbon dioxide from the atmosphere fairly readily and the resulting sodium carbonate is very insoluble in strong NaOH solution.


Which i have just nicely confirmed this by an experiment lol. Yeah it was a jumbled memory i didnt bother to check, i will get it all into solution and filter off my nice clean Nickel flakes.

Obviously the treatment with hot hydroxide was a washing step..... :cool:

I will plonk (technical term) into POTASSIUM hydroxide.

phlogiston - 4-3-2018 at 12:34

Potassium hydroxide solution will not dissolve nickel either.
I'm curious what wiki site said that it would.

Neither the wikipedia and the SM wiki site entries for nickel mention it. In fact the wikipedia site specifically mentions nickel being highly resistant to alkali and useful for storing sodium hydroxide and potassium hydroxide.

NEMO-Chemistry - 5-3-2018 at 02:02

Woelen i thought mentioned it on here.... and wikipedia now i got my glasses on says nickel 2 salts and potassium hydroxide not Nickel, so that was my mistake.

Which leaves me with a problem dissolving my nickel flakes!

NEMO-Chemistry - 5-3-2018 at 02:09

Forget it, I am in stupid mode today, Woelen was on about something else, looks like ferric chloride with HCl and then ammonia will dissolve it. No Hydrogen peroxide at the moment, its something i dont consider good to have around at the moment.