The discovery of molecules and atoms was the most importantan event in the development of the atomic-molecular theory. Back in 1748, the great Russian scientist Mikhail Vasilyevich Lomonosov formulated the law of conservation of the masses as a philosophical concept. Later, he himself summed up a powerful practical-theoretical basis for her proof, and it happened in 1756. Along with the Russian scientist, the French chemist AL Lavoisier worked on this problem. He proposed his version of evidence in 1789.
The law of conservation of mass of matter states that the sumthe masses of all substances that enter into a chemical reaction are numerically equal to the mass of substances that are the products of the reaction. The initial ways to practically prove, then, the assumption of the preservation of the masses were not crowned with success. The fact is that the experiments that were carried out before Lomonosov were based on the combustion of substances. Results of weighing before and after the reaction did not agree with the obvious, but not confirmed in practice theory. Heating the air with mercury resulted in a red scale, and its mass was greater than the mass of the reacting metal. With the ash that appears after the combustion of wood, the result was the opposite, the product mass always turned out to be less than the mass of the substance before the reaction was carried out.
The merit of Lomonosov is that he,to prove the law of conservation of mass, for the first time conducted an experiment with closed systems. Simplicity of experience once again proved the genius of the Russian scientist. Calcinated metals Lomonosov placed in a sealed glass vessel. After a successful reaction, the weight of the vessel remained unchanged. And only when the vessel was smashed, and the air rushed inward, there was an increase in the mass of the vessel.
Theoretical explanation of theexperiment was given by the connecting character of the metal burning reaction. The increase in mass was due to the addition of oxygen atoms to the oxidation product. Having proved the law of conservation of mass, Lomonosov made a significant contribution to the development of the atomic-molecular theory. In practice, he once again proved that atoms are chemically indivisible. The molecular structures change during the reactions, they exchange atoms among themselves, but their total number (atoms) in the closed system remains unchanged. Accordingly, the total mass of the substance is also constant.
The law of conservation of mass was the first contribution toknowledge of a more global natural pattern. Further studies in this direction have made it possible to reveal that in closed systems there is not only the preservation of the masses. The energy of an isolated system is also a constant. Any process that takes place in an isolated system does not produce or destroy either mass or energy. And the revealed regularity was later called: the law of conservation of mass and energy. The works of Lomonosov became only evidence of a special case of the greatest law of nature.
But on this knowledge of the world around us is notends. Einstein's works advanced science even further, in his theory he not only proved the interconnection of energy and mass, but also made a bold assumption about the possibility of their transformation. What now seems understandable to an ordinary schoolboy, was formed in the course of practical experiments and theoretical studies over the last three centuries. Scientists in the most diverse fields of natural science collected a powerful platform for the proof of the laws and the concept of "energy" and "mass".
Not only physics and chemistry, but also many otherssciences actively use the relationship and the principle of conservation of mass and energy. Biology, geography, astronomy find application of the law of conservation of mass and energy. Even philosophy under the influence of this law has formed a modern representation of man about being.
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