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Monday, 2 February 2015

Law Of Conservation Of Mass

law of conservation of mass


In 1748 formulated MW Lomonosov (1711-1765), the law of conservation of mass. The same law was AL Lavoisier (1743-1794), when he the reaction of metals with air (oxygen) investigated with the aid of the balance. The main merit of that research was the introduction of the scale in chemical works.

First chemical constitution

In a reaction, the mass of the substances concerned remains unchanged. The sum of the masses of the reaction products is thus equal to the sum of the masses of starting materials.

Mass of the starting materials = mass of the resulting materials


In 1756, Mikhail Lomonosov repeated this experiment Boyle and came to the conclusion that the phlogiston theory could not be true. Before Lomonosov opened the fed molten glass vessel, he placed a lighted candle in front of the opening. The candle flame was drawn at the moment of the opening in the vessel. Upon heating of lead in the sealed vessel was thus a part of the air "disappeared". The reaction product of the lead was now heavier than the lead before the experiment. Lomonosov wrote in his diary. "Today I conducted an experiment in hermetically sealed glass vessels, to see if the mass of a metal is larger under the mere action of heat The experiments of which I append a 13-page report, showed that the famous Robert Boyle was misled, because without access of air from outside the mass of burnt metal remained unchanged. ... It is the air particles that combine with the metals when heated, and this in turn limes ". The "limes" today would be described as metal oxides.

The Diamond

the diamonds\


Diamond is the cubic modification of carbon and as a naturally occurring solid mineral from the mineral class of elements. Diamond usually forms octahedral crystals, often with curved surfaces and streaky. Other forms observed are the tetrahedron, dodecahedron and the cube. The crystals are transparent, colorless or colored by impurities (eg., Nitrogen) or crystal lattice defects green, yellow, brown and rarely, orange, blue, pink, red or gray to black.

Diamond is the hardest natural substance. In the Moths hardness scale, he has the hardness of 10. His abrasive hardness Roswell (also absolute hardness) is 140 times greater than that of corundum. The hardness of the diamond is, however, different in different crystallographic directions (anisotropy). This makes it possible to grind diamond. In the diamond powder used for this purpose, the crystals are in any orientation before (statistical isotropy) so always worked the hardest of them on the body to be ground.


Diamond is optically isotropic with high refraction and high dispersion. He shows fluorescence and phosphorescence and is turboelectric. It has the highest thermal conductivity of all known minerals.