Aldehydes and ketones call two big groups of carbonyl connections. They are similar in chemical and physical properties, but differ structure and reactions.
Aldehydes and ketones are similar in structure, however, unlike aldehydes, two deputies have ketones. Aldehydes show big activity that is connected with properties of substance more to polarize chemical bonds.
Aldehydes
The simplest example of aldehyde – acetic. Chemists received this substance, oxidizing usual alcohol mixes of sulfuric acid, peroxide of manganese and dvukhromovokaliyevy salt. Long time aldehyde was called easy oxygen air. The scientist Libikh for the first time gave him a new name, having reduced the words "alcohol" and "obezvodorozhenny" – Alcohol and dehydrogeniatus – Aldehyd.
Aldehyde – colourless liquid with a pungent and suffocating smell. Thanks to the property to attach oxygen, aldehyde can turn into acetic acid which then began to be used for preservation of meat and many other food. Aldehyde is applied at production of green and violet aniline paints, successfully used in the aromatic industry and even in creation of fruit essences. In 1921 the personal perfumer Coco Chanel the first used aldehyde when he worked on creation of Chanel No. 5 spirits well-known for the whole world. Aldehydes also widely use at production of various pitches, plates, polyfoam, moisture-proof paper and cardboard. Also at mechanical engineering, for production of electrotechnical products, varnishes and glues. Formaldehyde is applicable in pharmaceutics and during creation of explosives.
Ketones
The most known type of ketone – acetone. It was opened in 1661 by Robert Boyle and comes from the Latin term acetum — vinegar. Ketones are toxic flying liquids and fusible solid substances. Can get through skin and render irritant action. Some ketones possess narcotic action. Substances of this group take part in metabolism of living organisms. Monosaccharides (for example, fructose), essential oils (camphor), (indigo) natural dyes, steroid hormones (progesterone), antibiotics (tetracycline) belong to the connections containing ketones in the structure. Use of the ketones extracted in the natural way is insignificant. Perhaps, only important is an acetone. In the industry ketones apply as solvents, as a part of polymers and in pharmacology. Availability of acetone in urine and blood of the person metabolism violations.