Vital forces theory

Urea [57-13-6] was discovered ia urine by Rouelle ia 1773 and first synthesized from ammonia (qv) and cyanic acid by Woehler ia 1828. This was the first synthesis of an organic compound from an inorganic compound, and it dealt a deathblow to the vital-force theory. In 1870, urea was produced by heating ammonium carbamate ia a sealed tube. 

The term organic chemistry was first used by the Swedish chemist Berzelius in 1807 (Larsson, 1981). He coined the name to describe the chemistry of substances derived from living matter. Berzelius was a staunch believer in the vis vitalis theory, which held that such substances were endowed with a mystical vital force that precluded their synthesis in the laboratory from materials of mineral origin. Ironically, it was a student of Berzelius, Wohler, who heralded the demise of vitalism with his synthesis of urea from ammonium cyanate (Wohler, 1928). In a letter to Berzelius in 1828, Wohler wrote I must tell you that I can make urea without requiring kidneys, or even an animal, whether a human being or a dog . 

Until the mid-eighteenth century, scientists believed organic compounds came only from live plants and animals. They reasoned that organisms possessed a vital force that enabled them to produce organic compounds. The first serious blow to this theory of vitalism, which marked the beginning of modern organic chemistry, occurred when Friedrich Wohler (1800-1882) synthesized urea from the two inorganic substances lead cyanate and ammonium hydroxide ... 

Variable one of any number of factors that change and may influence an observation or experimental outcome Viscosity the resistance to flow Vitalism theory that a vital force associated with life was associated with all organic substances... 

The history of organic synthesis is generally traced back to Wohler s synthesis of the natural product urea from ammonium isocyanate in 1828. This laid to rest the vis vitalis (vital force) theory, which maintained that a substance produced by a living organism could not be produced synthetically. The discovery had monumental significance, because it showed that, in principle, aU organic compounds are amenable to synthesis in the laboratory. 

Despite increasing acceptance by scientists, some people viewed the synthesis of natural compounds as unnatural. Indeed proponents of the vital force theory can still be found on a quick scan of the Internet more than 100 years after it was discredited as a scientific theory. For example, vestiges of the vital force theory linger in the belief that vitamins from natural sources are somehow healthier than vitamins that are synthesized. 

Vital-force theory The theory that a vital force determined the difference between organic and inorganic compounds. Organic materials isolated from plants and animals were thought to contain a vital force, while inorganic materials did not. 

Urea had always come from living organisms and was presumed to contain the vital force, yet ammonium cyanate is inorganic and thus lacks the vital force. Some chemists claimed that a trace of vital force from Wohler s hands must have contaminated the reaction, but most recognized the possibility of synthesizing organic compounds from inorganics. Many other syntheses were carried out, and the vital force theory was eventually discarded. 

Chemists of the period noted thaot there seemed to be an essential yet inexplicable difference between the properties of the two different types of compounds. The vital force theory (sometimes called vitalism ) was therefore proposed (and widely accepted) as a way to explain these differences. Vitalism proposed that there was a something called a vital force which existed within organic material but did not exist in any inorganic materials. 

Wohler s discovery refuted the vital force theory. In a letter to Berzelius, whom he had been associated with, Wohler wrote,... 

Ironically, Wohler, the first person to s)mthesize an organic compound from inorganic substances, devoted the rest of his career to inorganic chemistry. However, other chemists continued this work, and as a result, the "vital force theory" was laid to rest, and modern organic chemistry was born. 

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