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The Wöhler synthesis is the conversion of ammonium cyanate into urea. This chemical reaction was described in 1828 by Friedrich Wöhler. [1] It is often cited as the starting point of modern organic chemistry. Although the Wöhler reaction concerns the conversion of ammonium cyanate, this salt appears only as an (unstable) intermediate.
Wöhler synthesis of urea by heating ammonium cyanate. The Δ sign indicates the addition of heat. Wöhler's demonstration of urea synthesis has become regarded as a refutation of vitalism, the hypothesis that living things are alive because of some special "vital force". It was the beginning of the end for one popular vitalist hypothesis, the ...
As late as the 1840s, and despite Friedrich Wöhler's synthesis of urea in 1828, some chemists still believed in the doctrine of vitalism, according to which a special life-force was necessary to create "organic" (i.e., in its original meaning, biologically derived) compounds.
The synthesis of urea in the early 19th century from inorganic compounds was counterevidence for the vitalist hypothesis that only organisms could make the components of living things. Jöns Jakob Berzelius , one of the early 19th century founders of modern chemistry , argued that a regulative force must exist within living matter to maintain ...
1828 – Friedrich Woehler synthesized urea; first synthesis of an organic compound from inorganic starting materials. 1836 – Theodor Schwann discovered pepsin in extracts from the stomach lining; first isolation of an animal enzyme. 1837 – Theodor Schwann showed that heating air will prevent it from causing putrefaction.
He synthesized urea by slowly evaporating a water solution of ammonium cyanate, which he had prepared by adding silver cyanate to ammonium chloride. It has been previously believed that, the substances produced by plants and animals (by generally all living beings or organisms) can not be produced in lab and can only be produced by "life force".
The Miller–Urey experiment was a synthesis of small organic molecules in a mixture of simple gases in a thermal gradient created by heating (right) and cooling (left) the mixture at the same time, with electrical discharges.
Hemodialysis, also spelled haemodialysis, or simply dialysis, is a process of filtering the blood of a person whose kidneys are not working normally. This type of dialysis achieves the extracorporeal removal of waste products such as creatinine and urea and free water from the blood when the kidneys are in a state of kidney failure.