<P> By the 18th century the principle of conservation of mass during chemical reactions was widely used and was an important assumption during experiments , even before a definition was formally established , as can be seen in the works of Joseph Black , Henry Cavendish , and Jean Rey . The first to outline the principle was given by Mikhail Lomonosov in 1756 . He demonstrated it by experiments and had discussed the principle before in 1774 in correspondence with Leonhard Euler , though his claim on the subject is sometimes challenged . A more refined series of experiments were later carried out by Antoine Lavoisier who expressed his conclusion in 1773 and popularized the principle of conservation of mass . The demonstrations of the principle led alternatives theories obsolete , like the phlogiston theory that claimed that mass could be gained or lost in combustion and heat processes . </P>
<P> By the 18th century the principle of conservation of mass during chemical reactions was widely used and was an important assumption during experiments , even before a definition was formally established , as can be seen in the works of Joseph Black , Henry Cavendish , and Jean Rey . The first to outline the principle was given by Mikhail Lomonosov in 1756 . He demonstrated it by experiments and had discussed the principle before in 1774 in correspondence with Leonhard Euler , though his claim on the subject is sometimes challenged . A more refined series of experiments were later carried out by Antoine Lavoisier who expressed his conclusion in 1773 and popularized the principle of conservation of mass . The demonstrations of the principle led alternatives theories obsolete , like the phlogiston theory that claimed that mass could be gained or lost in combustion and heat processes . </P>
who came up with the conservation of mass
who came up with the conservation of mass
Mikhail Lomonosov
Mikhail Lomonosov