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Arsenic is a chemical element with the ... bacteria were discovered that employ a version of photosynthesis in the ... (early in the year, focusing on urinary ...
The first breakthrough in the detection of arsenic poisoning was in 1775 when Carl Wilhelm Scheele discovered a way to change arsenic trioxide to garlic-smelling arsine gas (AsH 3), by treating it with nitric acid (HNO 3) and combining it with zinc. [3] As 2 O 3 + 6 Zn + 12 HNO 3 → 2 AsH 3 + 6 Zn(NO 3) 2 + 3 H 2 O
Perey discovered it as a decay product of 227 Ac. [177] Francium was the last element to be discovered in nature, rather than synthesized in the lab, although four of the "synthetic" elements that were discovered later (plutonium, neptunium, astatine, and promethium) were eventually found in trace amounts in nature as well. [178]
Arsenic was known to be poisonous during the Victorian era. [103] Beginning in about 3000 BC arsenic was mined and added to copper in the alloying of bronze, but the adverse health effects of working with arsenic led to it being abandoned when a viable alternative, tin, was discovered. [104]
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]
Although she had had access to arsenic, and arsenic had been found in the victim's food, none could be found in the corpse. Orfila was asked by the court to investigate. He discovered that the test used, the Marsh test, had been performed incorrectly, and that there was in fact arsenic in the body; LaFarge was subsequently found guilty.
Robert Wilhelm Eberhard Bunsen (German:; 30 March 1811 [a] – 16 August 1899) was a German chemist.He investigated emission spectra of heated elements, and discovered caesium (in 1860) and rubidium (in 1861) with the physicist Gustav Kirchhoff. [11]
In the 18th century, William Withering discovered that arsenic trioxide, when used in small doses, exhibited therapeutic effects. [6] During the same period, Thomas Fowler prepared a 1% solution of arsenic and potassium carbonate, which was used to treat skin diseases (primarily psoriasis) until the 20th century. [7]