Red Solution - what did I do?

[didit]

Always keep Mercury separate.
When you suspect Hg always test.

But in this case it should not be enough to create this kind of problem should it?
You are the one who knows how much it could be.

That's good point. It should be that much mercury at all even if there is some and there is definitely an awful lot of precipitate. I'll try to re acidy the flask later this evening and see where that gets me.

 

[Alondro]

So now I am curious if by adding Sodium Hydroxide did I basically precipitate yellow mercury(II) oxide (HgOHgO)?

Looking up reactions, it appears that mercury oxide is indeed synthesized by the addition of alkali to aqueous solutions of mercury cations. It is a yellow to red solid and fits very well with what you have there.

It's possible it's also platinum chloride, which is insoluble in neutral to basic solutions not containing amonia.

 

[didit]

Looking up reactions, it appears that mercury oxide is indeed synthesized by the addition of alkali to aqueous solutions of mercury cations. It is a yellow to red solid and fits very well with what you have there.

Yes it does doesn't it.

I just got home from work and am about to add some HCl to re-acidify the solution as suggested by Yggdrasil and see if the remaining precipitate goes back into solution. I will update you all shortly.

 

[Alondro]

Yes it does doesn't it.

I just got home from work and am about to add some HCl to re-acidify the solution as suggested by Yggdrasil and see if the remaining precipitate goes back into solution. I will update you all shortly.

I added that it could also be platinum chloride, since that's insoluble in neutral or basic solutions, unless sufficient ammonia is present.

Both platinum chloride and mercury oxide will go back into solution with HCl, so that won't be very telling. The mercury will become a chloride salt again.

 

[didit]

I added that it could also be platinum chloride, since that's insoluble in neutral or basic solutions, unless sufficient ammonia is present.

Both platinum chloride and mercury oxide will go back into solution with HCl, so that won't be very telling. The mercury will become a chloride salt again

Did you re acidify yet?

I see your point Alondro. I would however like to get my gold. If there is more mercury or platinum in solution could I not just add Sodium Hydroxide again after I drop the gold. If using SMB it should only drop the gold correct?

Anyway, I already added a dose of HCl to one flask solution and this is the result.

pH is about 1 now.

 

[didit]

Does anyone have an image of what Gold(III) hydroxide looks like?

 

[Yggdrasil]

Does anyone have an image of what Gold(III) hydroxide looks like?

I do not think Gold forms Hydroxides at this pH.
But it is yellow like this:
https://www.samaterials.com/gold-hydroxide-powder.html

 

[Alondro]

I see your point Alondro. I would however like to get my gold. If there is more mercury or platinum in solution could I not just add Sodium Hydroxide again after I drop the gold. If using SMB it should only drop the gold correct?

Anyway, I already added a dose of HCl to one flask solution and this is the result.

pH is about 1 now.

SMB should only drop the gold.

You can test for mercury in the remaining solution this way: add a few drops of solution to a couple milliliters of 5M sulfuric acid. Then drip this solution into distilled water. If mercury is present, the mercury sulfate will decompose into yellow mercury subsulfate, which is totally insoluble in water. The platinum salts will remain in solution, unless some Pt(II)Cl2 has formed, which will fall out as brown 'mud'.

You can then also drip a drop of the sulfate solution into a little test tube of 100% ethanol. White mercury sulfate crystals will drop out. With these two tests giving precipitates as described, it's strongly positive for the presence of mercury.

If there's either form of platinum chloride in the solution, brown precipitate will form in ethanol. Pt(II) chloride is totally insoluble in alcohol, and Pt(IV) chloride is only slightly soluble in alcohol. If the Pt is entirely in the form of hexachloroplatinic acid, however, I do not believe a precipitate will form.

Always remember that either Hg or Pt in solution are highly toxic!