Lavoisier

Ever heard of the phlogiston theory? No?! Well, if you've never heard of it, it's safe to say that it's one theory that's been disproven.This theory stated that fire, or combustion, was made up of an element called phlogiston. Scientists thought that when things burned they released phlogiston into the air. During the late 18th Century, Antoine Lavoisier disproved the phlogiston theory. He is one of the founders of modern chemistry. He was quite wealthy, and this allowed him to obtain some of the best equipment available at the time, and allowed him spend his time conducting experiments (check out the pic). He eventually demonstrated that there was an element, which he named oxygen, that played a major role when substances burned. After hundreds of experiments and very careful measurement he showed that the mass of products in a reaction are equal to the mass of the reactants. In other words, no mass is lost in a chemical reaction. This became known as the Law of Conservation of Mass. We attempted to prove this law with our Alka-Seltzer experiment!