They had a bunch of faulty theories about it. Nowadays we know what happens when certain things react with oxygen at high temperatures. However Lavoisier did not know any of this. He discovered that when phosphorus, or sulfur, was burned in the air the products were acidic. This then led to the suggestion that elements combines with something in the air could produce acids. In 1779 he named oxygen and found out oxygen made up 20% of air. He also found out it was vital for combustion and respiration. He found out that the reaction phosphorus and sulfur had was formed by the reaction of the elements with oxygen. This finding proved that phlostigon was false. Lavoisier also named the element hydrogen. He burned hydrogen with oxygen and saw that it made water. He established that water isn’t an element, but is a compound made from these two elements. This finding shocked everyone because they all thought water was an invisible …show more content…
An example of this is finding out when mercury oxide is heated it’s weight decreases. After doing more and more observations he creates the law of conservation of mass. The conservation of mass is a principle stating that mass cannot be created or destroyed. Many think he was the first to state this, but this is false. The first to state this was actually Jean Ray who had come up with a similar law. This law only became established after Lavoisier discovered it. Lavoisier produced his book Elementary Treatise on Chemistry. In this book he states the difference between a compound and an element, since so many people did not know the difference. This book also included the idea that light was a chemical element. He also stated in his book that there was a substance called caloric. This was later proven false. In 1791 he was on the committee of French Academy of Sciences. They developed the metric system.
Although he did a lot for science he also did things in different fields. He bought a company that gathered tax from the government. He tried to reform tax law to help taxpayers who were poor. He also helped improve the quality of