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The Marsh test is a highly sensitive method in the ... Adding a sample of tissue or body fluid to a glass vessel with zinc and acid would produce arsine gas if ...
James Marsh (2 September 1794 – 21 June 1846) was a British chemist who invented the Marsh test for detecting arsenic. Born in Kent, he was working as a labourer in Woolwich in the late 1810s and early 1820s, before joining the Royal Artillery. [ 1 ]
The old (but extremely sensitive) Marsh test generates AsH 3 in the presence of arsenic. [4] This procedure, published in 1836 by James Marsh, [18] is based upon treating an As-containing sample of a victim's body (typically the stomach contents) with As-free zinc and dilute sulfuric acid: if the sample contains arsenic, gaseous arsine will ...
Devarda's alloy is a reducing agent that was commonly used in wet analytical chemistry to produce so-called nascent hydrogen under alkaline conditions in situ.In the Marsh test, used for arsenic determination, hydrogen is generated by contacting zinc powder with hydrochloric acid.
As stibine (SbH 3) is similar to arsine (AsH 3); it is also detected by the Marsh test. This sensitive test detects arsine generated in the presence of arsenic. [5] This procedure, developed circa 1836 by James Marsh, treats a sample with arsenic-free zinc and dilute sulfuric acid: if the sample contains arsenic, gaseous arsine will form. The ...
As the symptoms of arsenic poisoning are not very specific, the substance was frequently used for murder until the advent in the 1830s of the Marsh test, a sensitive chemical test for its presence. (Another less sensitive but more general test is the Reinsch test.) Owing to its use by the ruling class to murder one another and its potency and ...
In the Marsh test, used for arsenic determination (from the reduction of arsenate (AsO 3− 4) and arsenite (AsO 3− 3) into arsine (AsH 3)), hydrogen is generated by contacting zinc powder with hydrochloric acid. So, hydrogen can be conveniently produced at low or high pH, according to the volatility of the species to be detected.
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