polsol - 10-4-2006 at 00:26
Hi all,
I need to make up some aqueous hydrogen sulphide solution for testing the approximate (Nessler tube method) quantity of heavy metals in water.
Any idea of what the 'standard' concentration of H2S should be for this purpose? I'm aimimg to make the solution from FeS/HCl in a (very) rudimentary
piece of apparatus (in a fume cupboard of course).
This is something that was dumped on me at the last moment and trying to get hold of any technical books (like Vogel) is impossible here in the desert
except via importation (which would be too late).
Comparisons will be made againts a series of PbNO3 standards and results quoted as 'Heavy Metals (as Pb)'.
leu - 10-4-2006 at 04:12
Aqueous solutions of hydrogen sulfide are unstable, decomposed by oxygen in a few days. Other sulfides can be used to produce hydrogen sulfide, and
dilute sulfuric acid will work as well. One volume of water at 20 degrees dissolves 3.1 volumes of hydrogen sulfide