Question

to prove the law of conservation of mass

Answer 1

The Law of Conservation of Massstates that substances involved in chemical reactions do not lose or gain any detectable mass. The state of the substance, however, can change. For instance, the Law of Conservation of Mass should prove that an ice cube will have the same mass as the water that forms as the cube melts.

Answer 2

No, because mass is not conserved - mass is a state of energy - it changes with temperature and stress, and likely with changing cosmological factors, The same amount of mass configured as a shell will have a different energy than when configured as solid sphere. And vice versa. - To satisfy the law of conservation of energy, would require a greater mass for a shell configuration than a solid sphere - configuration takes into account the effect of gravity acting upon gravity. Bare mass is less that block mass. Take a sold block of mass M and separate it into tiny elements and spread them far apart such that there is insignificant gravitational interaction - it will have less mass This is called the bare mass. There are several special types of mass that arise in physics
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