Why did the work of Antoine Lavoisier and Joseph Priestley's work change people's ideas about burning?

Answer 1

　

1.burning has been important to people ever since early humans learnt how to control fire. But HOW do things burn? This was a question which it took centuries to answer - and until it could be answered, chemistry could never make much progress. By the 17th century scientists were beginning to realise that the burning of fuels, the reactions of metals in air and the breathing of animals all had something in common - they were all faster or slower versions of the same type of reaction. Wood turnss to ashes when it burns.

　

2. It made correct predictions of heat transfer, neglecting radiative heat transfer, and did not provide specifics of why certain materials had an "affinity" for phlogiston over other materials.

　

3.It is believed that matter is made from the elements air, water, and 3 elements of earth terra pinguis (fatty earth), mercurial, and fusible. On combustion it was thought that the fatty, combustible earth burnt away during combustion. In 1703 George Stahl renamed the terra pinguis as phlogiston, to take into account the corrosion of metals to be the "matter and principle of fire, not the fire itself". Contained in all combustible matters escaping from all burning material. For example a piece of wood turning to ashes on burning, the burning is explained by the escape of the phlogiston from the wood originally composed of ashes and phlogiston.

4.

Answer 2

Lavoisier did not discover combustion. He conducted experiments that disproved the old phlogiston theory of combustion and replaced it with the reasoning that combustion involved oxygen from the air. The old 'phlogiston' was a theoretical substance that never existed. This was the beginning of an understanding that energy was not a substance.