Marsh Test

The highly sensitive Marsh test is used to detect arsenic in food or stomach contents. The sample is mixed with zinc and sulphuric acid, any arsenic present causing the production of arsine gas and hydrogen. The gas is then led through a tube where it is heated strongly, decomposing into hydrogen and arsenic vapour. When the arsenic vapour impinges on a cold surface, a mirror-like deposit of arsenic forms. The same result can be produced by antimony, but the deposit is tested with sodium hypochlorite. Arsenic dissolves in this compound, while antimony does not. Before the invention of the Marsh test, arsenic had been a popular choice for poisoners because of the difficulty of detecting it. When the test was devised by the English chemist James Marsh in 1832, as a substitute for the less reliable hydrogen sulphide test, deliberate arsenic poisoning became rarer.

 

<< PreviousWord BrowserNext >>
united world colleges
uwc
eduardo parra
juana parra
claudio parra
mario mutis
high explosive squash head
william henry pope
barnett newman
john william ritchie
national assembly for wales
piat
tillie's punctured romance (1914 film)
ambrose shea
federal election commission
james montgomery flagg
adverse pressure gradient
tienne paschal tach
samuel leonard tilley
bazooka
lead(ii) nitrate
domrmy la pucelle
bartholomew roberts
kip thorne
flanger
ride
sigmaringen
london company
arsine
the universe in a nutshell
elimination reaction
nitrogen dioxide
lonesome dove
bantam spectra
stefan dragutin
stefan radoslav
sadyattes
principality of zeon
andrzej badenski
metropolitan state university
ilya prigogine
public school (uk)
mobile suit gundam 0083: stardust memory
morgan county