Until the nineteenth century, the names of organic compounds were given arbitrarily, only remembering their origin or any of their characteristics. Thus, for example, H - COOH was called formic acid because it was found in certain ants. As the number of organic compounds increased, the situation became so complicated that the chemists gathered at the Geneva International Congress in 1892 decided to start rationalizing the organic nomenclature.
Vacuum: That is not occupied by anything; that contains nothing; Empty, dumped. Space in which there is no atmospheric pressure. Absolute or almost absolute emptying, or external air or gas rarefaction. The empty space that is supposed to exist between the celestial bodies. vaporization: Change from liquid to gaseous state.
The chemical elements are grouped into three major groups: metals, nonmetals and noble gases. Hydrogen (H) does not fit into any of these classifications because it has its own characteristics. Some tables show this division. Metals are chemical elements that have several specific properties, such as gloss, thermal and electrical conductivity, malleability and ductility.
Starting from the Huygens Principle, we can explain another wave phenomenon, diffraction. The phenomenon called diffraction is the bending suffered by wave rays when it encounters obstacles to propagation. Imagine the situation where a wave propagates in a medium as far as it finds a crack in a barrier.
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Amide is any organic compound theoretically derived from ammonia (NH 3) by the replacement of a hydrogen atom with an acyl group. The generic formula for amides is: Some amides: Utility The best known amide is diamide, urea. It is a white, crystalline and water soluble solid.