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Specialty Chemistry Forums => Citizen Chemist => Topic started by: P-man on November 24, 2005, 05:53:32 PM

Title: Experiment hunting
Post by: P-man on November 24, 2005, 05:53:32 PM

I am on the hunt for basic experiments to post on my website. Any contributions well recieved.

Title: Re:Experiment hunting
Post by: Alberto_Kravina on November 25, 2005, 02:20:02 PM

Here is my favourite experiment: the Marsh test:

Quote

method for the detection of arsenic , so sensitive that it can be used to detect minute amounts of arsenic in foods (the residue of fruit spray) or in stomach contents. The sample is placed in a flask with arsenic-free zinc and sulfuric acid. Arsine gas (also hydrogen) forms and is led through a drying tube to a hard glass tube in which it is heated. The arsenic is deposited as a “mirror” just beyond the heated area and on any cold surface held in the burning gas emanating from the jet. Antimony gives a similar test, but the deposit is insoluble in sodium hypochlorite, whereas arsenic will dissolve. The test was named for its inventor, the English chemist James Marsh.