silver fulminate issue

[ssdd]

The other day I decided to make some silver fulminate, I used and followed the procedure from the Chem Lab here. But I encountered a few issues and was wondering if anyone had any ideas that could help me out next round.
1. While I was dissolving the Silver into the Nitric Acid I couldn't get the full gram of silver to dissolve. I heated it further as was suggested but stopped when I hit 50*C. (I Eventually added more acid...) Why didn't all of it dissolve?
2. After all other steps were followed I went to finally filter out the crystals from the milky white solution that had formed. My problem is that very little was yielded (not even enough to be set off...) and my guess is that it is due to the previous problem. The crystals were very small and were gray when they dried, I am fairly sure this is how it should have turned out.
Any ideas anyone? I know I am risking getting banned by asking but this seems to be the only place where I could find people who may know the answer.

[Shalashaska]

Although I am by no means familiar with fulminates, you didn't specify the concentration of your HNO3, which might be the problem, unless of course it's white fuming. (Very high, i.e. >97%)

[Flamethrowa]

A friend of mine who made double salts once had trouble dissolving the silver. IIRC he got it going by adding some water.

[ssdd]

I am using 15.8 molar fuming nitric acid....
the silver I believe is pure but appears to be reclaimed (this may be the issue now that i think about it...)
the ethyl was 95%
and so on

Wouldn't water have to opposite effect though, because it would weaken the nitric acid and less silver would probably get reacted... perhaps ill try it on a small scale to see what happens... ;)

[nbk2000]

Lack of paragraph breaks and capital I's has resulted in a weeks vacation for ssdd. ;)

[blank]

Most likely the HNO3 needs to be diluted. I don't think silver purity should be too much of a problem either. For making double salts, I use a silver coin with 10% copper. I remember the first time trying to dissolve my silver. I was using 70% HNO3 and the silver was hardly dissolving at all. I then diluted the HNO3 to twice its volume with water and it started to dissolve rapidly. I believe the reason dilute HNO3 works better is because the acid needs water to dissolve the AgNO3 as it forms on the surface of the metal.

[megalomania]

Concentrated nitric acid passivates (look it up) metals, but dilute nitric acid does not.

[prufrock]

It can be determined from the literature that when making silver fulminate, one determines the quanity of silver required for the reaction from silver nitrate, I believe silver nitrate is 63.5% silver, thus if the formula requires one gram of silver, you would use 1.575 grams of silver nitrate to yield one gram of ionic silver.

Dissolve the silver nitrate in dilute nitric acid because one wants the aqueous environment to be rich in nitrate ions.

From a different perspective, when you dissolve metallic silver in dilute nitric acid, and reduce the volume of water one precipitates silver nitrate crystals.

[ssdd]

Ok I'm back. I will try to keep my grammar in check from here out. :rolleyes:

+++++++++

And with the :rolleyes: he pissed away his warning. :rolleyes:

NBK