Directions: Read the background text and then answer all questions labeled classwork. You will answer questions based on the four experiments that Lavoisier ran in order to prove his theory of Conservation of Mass.
Antoine Lavoisier was a French chemist who did most of his work between 1772-1786. He built a magnificent laboratory in Paris, France and invited scientists from around the world to come and visit. Lavoisier conducted numerous controlled experiments. He published two textbooks that helped organize chemistry into a comprehensible science. Based on his contributions to chemistry, Lavoisier is commonly known as the Father of Modern Chemistry.
Lavoisier’s most famous experiments involved the combustion of substances such as phosphorus, sulfur, and mercury. He proposed that air is composed of two parts, one of which combines with metals to form new products. This part was later named oxygen. Lavoisier believed that when a substance burns, oxygen from air combines with that substance to form a new substance. His experiments showed that the new product weighed more than the original substance by a mass equal to the amount of oxygen that reacted with the substance.
These experiments led to what is currently known as The Law of Conservation of Mass. This law states that mass can neither be created nor destroyed. It can only be converted from one form to another. Initially, Lavoisier’s conclusions were not accepted by the scientific world but they eventually led to a revolution in chemical thought. His work ultimately led to the basis of Dalton’s Atomic Theory.
Classwork: How did Lavoisier's work contribute to our understanding of the composition of air?