NEMO-Chemistry
International Hazard
Posts: 1559
Registered: 29-5-2016
Location: UK
Member Is Offline
Mood: No Mood
|
|
Dimethylglyoxime
I have read wikipedia etc, it all mentions using it for the detection of
Nickel.
What it dosnt tell me is how much of the powder to use in solution...
I have 5g which was pretty expensive, as i am doing things with Nickel chemistry i thought it would allow me to quantify the amount of nickel, now i
could just 'mix' some with DI water and use that.
I understand that if i was to use it to titrate then i simply take its molecular weight (116.2/mol) and make a X mm solution.
But how much would you use in say 200ml of DI water to keep as a stock solution to just detect the presence of Nickel?
[Edited on 13-6-2018 by NEMO-Chemistry]
|
|
|
Aqua-regia
Hazard to Others
Posts: 126
Registered: 18-12-2006
Member Is Offline
Mood: No Mood
|
|
DMG is mainly uses in 1% ethanolic solution. Not soluble in water. If you have a solution containing Ni, buffering it to pH 8, and add a few ml 1%
DMG alcoholic solution. It is forming a raspberry red precipitat.
A typical gravimetric estimation of the nickel, byside iron and copper:
If you have 0,13-0,17 g dissolved nickel ions in the beaker, complexise the other metallic ions with 20 ml 20% tartaric acid solution, heat the
soln carefully till 40-45 degrees, add 15 ml 20% Na2S2O3 soln, buffering with HCL pH 4-4,5. Few minits later add into the beaker 65 ml 1% ethanolic
DMG soln. Puffering pH than pH 8-8,5 with NH3 soln, keep it in 45 degrees a half an hour, the Ni-DMG will 100% precipitated, you can filtering with
G3 fritted filter, washing twice with 10 ml water. Drying at 120 degrees 2 hours.
[Edited on 13-6-2018 by Aqua-regia]
|
|
|
NEMO-Chemistry
International Hazard
Posts: 1559
Registered: 29-5-2016
Location: UK
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by Aqua-regia  | DMG is mainly uses in 1% ethanolic solution. Not soluble in water. If you have a solution containing Ni, buffering it to pH 8, and add a few ml 1%
DMG alcoholic solution. It is forming a raspberry red precipitat.
A typical gravimetric estimation of the nickel, byside iron and copper:
If you have 0,13-0,17 g dissolved nickel ions in the beaker, complexise the other metallic ions with 20 ml 20% tartaric acid solution, heat the
soln carefully till 40-45 degrees, add 15 ml 20% Na2S2O3 soln, buffering with HCL pH 4-4,5. Few minits later add into the beaker 65 ml 1% ethanolic
DMG soln. Puffering pH than pH 8-8,5 with NH3 soln, keep it in 45 degrees a half an hour, the Ni-DMG will 100% precipitated, you can filtering with
G3 fritted filter, washing twice with 10 ml water. Drying at 120 degrees 2 hours.
[Edited on 13-6-2018 by Aqua-regia] |
Thank you for the info, that will teach me to make assumptions on water solubility!! Silly mistake on my part. The information you have given is most
helpful.
Looks like a unusual colour for a Nickel complex, nice raspberry red. Out of interest do you have any idea if Methanol can be usd instead of ethanol
for a 'quick n dirty' Nickel test?
|
|
|
UC235
National Hazard
Posts: 565
Registered: 28-12-2014
Member Is Offline
Mood: No Mood
|
|
DMG is not a terribly difficult synthesis. I have run this prep before. It works as advertised: http://www.orgsyn.org/Content/pdfs/procedures/CV2P0204.pdf
|
|
|
DraconicAcid
International Hazard
Posts: 4278
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
Methanol should be fine.
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.
|
|
|
NEMO-Chemistry
International Hazard
Posts: 1559
Registered: 29-5-2016
Location: UK
Member Is Offline
Mood: No Mood
|
|
thats good i got plenty of that.
i will look the prep up as it isnt cheap to buy
|
|
|
Aqua-regia
Hazard to Others
Posts: 126
Registered: 18-12-2006
Member Is Offline
Mood: No Mood
|
|
If you are teacher use rectified spirit instead meOH. Toxicology!!!
|
|
|
XeonTheMGPony
International Hazard
Posts: 1636
Registered: 5-1-2016
Member Is Offline
Mood: No Mood
|
|
lol.
(I have worked with 45 gallon barrels of the stuff, been arms deep in it, short of drinking it, or standing in a tiny tiny room with massive amounts
evaporating you'd be very hard pressed to be poisoned by it.
So I can say with out a doubt working with tiny amounts we're talking of here it is delusional to be even concerned about it. Other guys washed their
hands with it, washed out cuts *Now that I'd agree bad idea!*)
But this just shows how modern day hysteria is effecting the newer generations
It is good to be mind full of its properties, but one must all so realize reality, a kid would be more likely to chance drinking it if he knows it is
"grain alcohol" then if he knows it is a poison, and only so much so IF you drink it!
(Given usage in this context you won't be bathing in it nor inhaling large amounts)
|
|
|
Aqua-regia
Hazard to Others
Posts: 126
Registered: 18-12-2006
Member Is Offline
Mood: No Mood
|
|
"But this just shows how modern day hysteria is effecting the newer generations"
This is just a question about the taking of risk and responsibility of teacher nothing else. Iam personally not belong the new generation , but I had
been a witness a lab poisoning with meOH. The guy got blindness. He mixed an alcoholic coctail in the lab, but used meOH....
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
