The law of conservation of mass was first discovered by Russian scientist lomonosov in 1756. Lavoisier found through a large number of quantitative experiments that in chemical reactions, the total mass of substances participating in the reaction is equal to the total mass of substances generated after the reaction. This law is called the law of conservation of mass. Also known as the law of immortality of matter. It is one of the basic laws prevailing in nature.

2, the law of conservation of charge

In physics, the law of charge conservation is about the law of charge conservation. There are two versions of the law of conservation of charge, the weak version (also known as the global law of conservation of charge) and the strong version (also known as the local law of conservation of charge). The weak version of the law of conservation of charge shows that the total charge of the whole universe remains unchanged and will not change with the evolution of time.

3. Law of Conservation of Energy

The law of conservation of energy, the first law of thermodynamics, means that the total energy in a closed (isolated) system remains unchanged. Generally speaking, total energy is no longer just the sum of kinetic energy and potential energy, but the sum of static energy (internal energy), kinetic energy and potential energy? .

The law of conservation of energy can be expressed as follows: the change of total energy of a system can only be equal to the amount of energy transmitted into or out of the system. Total energy is the sum of mechanical energy, thermal energy and any form of internal energy except thermal energy.

Extended data

Since Einstein put forward the special theory of relativity and the formula of mass-energy relationship E=mc? Then it shows that matter can be converted into radiant energy, and radiant energy can also be converted into matter. What effect does this conclusion have on the application of the law of conservation of mass in chemistry? The experimental results show that the energy released after the explosion of 1000g nitroglycerin is 8.0×10 6j6j.

According to the mass-energy relationship, the mass of these energies is 8.9× 10-8g, which is too small to be measured by experimental technology compared with the original 1000g. From a practical point of view, the law of conservation of mass is completely correct.

Since the 20th century, it has been found that the energy produced by nuclear fission far exceeds the most violent chemical reaction. As a result of the fission of 1000g uranium 235, the released energy is 8.23x10/6j, which is equivalent to the mass of these radiant energies of 0.9 14g. Compared with the original 1000g, the quality change has reached one thousandth. So people have a new understanding of the law of conservation of mass. Before the 20th century, scientists recognized two independent basic laws: the law of conservation of mass and the law of conservation of energy.