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rasendra
01-11-2012, 05:26 AM
Frndz.

I wana know how to test gold particles in silver or copper or led? If i add 0.5 gm gold in 10 gm silver or copper or led, n dissolve in nitric acid, then how to test present gold particles by easy chemical reagents or, or by easy process?

rogerc
01-11-2012, 06:34 AM
Frndz.

I wana know how to test gold particles in silver or copper or led? If i add 0.5 gm gold in 10 gm silver or copper or led, n dissolve in nitric acid, then how to test present gold particles by easy chemical reagents or, or by easy process?

You can test gold in solution with a simple stannous chloride test.

rasendra
01-11-2012, 07:32 AM
Please explain me in detail by stanneous chloride

asta
01-11-2012, 09:22 AM
Nitric acid won't dissolve gold. You need aqua regia or a high-concentrated chlrorine solution, wich is a dangerous method.

Once you have gold in solution, take some chlorhydric acid and pure tin, boil it until it dissolves, and then take a drop of your gold solution and a mix it with a drop of your stanneous chloride. If it turn purple-black, there's gold present.

rasendra
01-11-2012, 02:29 PM
Frndz any other test directly upon gold compound? Or easy test by any other chemical for very small amount of gold in au-cu or au-ag, or pb-au compound

pneumatician
01-19-2012, 03:09 AM
Nitric acid won't dissolve gold.

nitric acid dissolve gold :) read the wikipedia, well in quantity of atoms, but dissolve

asta
01-19-2012, 12:46 PM
nitric acid dissolve gold :) read the wikipedia, well in quantity of atoms, but dissolve


Some precious metals, such as pure gold do not react with nitric acid, though pure gold does react with aqua regia, a mixture of concentrated nitric acid and hydrochloric acid.

From: http://en.wikipedia.org/wiki/Nitric_acid

pneumatician
01-19-2012, 04:50 PM
From: http://en.wikipedia.org/wiki/Nitric_acid

Com funciona

Tot i que l'aigua rŔgia dissol els metalls abans mencionats, cap dels seus Ócids constituents pot fer-lo per si sol. L'Ócid nÝtric Ús un potent oxidant, que pot dissoldre una quantitat min˙scula (prÓcticament indetectable) d'or, formant ions d'or.

http://ca.wikipedia.org/wiki/Aigua_r%C3%A8gia

from wp in catalonian -> "Nitric acid is a potent oxidant, which can dissolve a tiny amount (almost undetectable) of gold, forming gold ions."

what understand this people for "tiny amount" & "almost undetectable" is a big mistery!

well, remenber Homeopathy, ORMUS...

pneumatician
01-23-2012, 03:00 AM
Frndz.

I wana know how to test gold particles in silver or copper or led? If i add 0.5 gm gold in 10 gm silver or copper or led, n dissolve in nitric acid, then how to test present gold particles by easy chemical reagents or, or by easy process?

uh ? if you mix 0,5 grams with 10 grams and dissolve the 10 grams you have... 0,5 gms ??? :) well hey, around 0,5...

So be, reduce to dust the acid solution, wash the salts and pours part of the 0,5 grms of "something" in melted transparent glass, if the cold glass is sky-colored is Au
if yellow is Ag
sea green is Cu
'duskisl' is lead

in any basic book of chem you can find some test like by sulfide current, iron sulfate, oxalic or tartaric acids...