iandol on sun 7 apr 02
Dear Marianne Lombardo <>
You ask <would be used for food/drink has lead in the glaze. Other than lab =
testing.>>
I'm uncertain but I would like to float this idea for the others to =
think about.
If you take the fluid resulting from the vinegar or lemon leach test it =
should be possible to add a substance to that which will react with lead =
in solution so that it reveals itself. The Chemists in the group might =
wish to confirm that Lead can be precipitated as Lead Chloride with =
Hydrochloric acid giving a white precipitate, with Potassium chromate a =
yellow precipitate and with Ammonium sulphide a black precipitate. If =
there are only very small amounts the first might be inadequate because =
Lead chloride is slightly soluble. You might also get other cations =
being precipitated such as Copper and Iron which would mask the test. =
But it is worth thinking about.
Upper high school science students should be able to do qualitative =
separations if you provided them with a sample.
Best regards,
Ivor Lewis. Redhill, South Australia.
Best regards,
Ivor
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