Timeline Of Chemistry

The timeline of chemistry has many important discoveries, ideas and experiments that changed people's understanding of the modern science known as chemistry. There are currently 118 elements known by mankind but it has taken a long time to get to where we are today. Over this long period of time many scientists have experimented and discovered things that are correct even today and some discoveries that are not. This assignment is going to be about the main scientists that had vast contributions to chemistry.
Democritus has changed science forever with his theories. He was known to have vast knowledge in science and philosophy. Hi is mostly associated with the founding of the atomic theory of matter. According to Democritus all matter is made

He sustained that all substances which burned contained a flammable source called phlogiston (from the Greek word meaning a flame) which was lit during the ignition process. This principle of phlogiston is shown not only in such obvious combustible substances as wood, wax, oils, and other organic materials but also in inorganic substances such as metals etc.
Joseph Priestley was mostly known for his work with the chemistry of gases. He later experimented with several distinctive types of “air”. In the past, scientists believed that the air on Earth contained only carbon dioxide and hydrogen. Priestley brought 5 more gases to this list, such as nitrogen, hydrogen chloride, carbon monoxide, nitrous oxide and oxygen.
Lavoisier's main achievement was his role in the pulling apart the phlogiston theory of combustion. Phlogiston was an element thought to be released during combustion of metals. Former chemists, like Germans Johann Becher and George Stahl, thought that a metal was composed of phlogiston, and that burning it caused loss of phlogiston. The statement was that metals actually gain weight during combustion which was usually explained away by the theory that phlogiston had negative weight. Lavoisier, like some others, knew that it was unscientific for anything to have negative

He used his gold foil experiment he discovered Rutherford scattering off the nucleus. His gold foil experiment helped describe the nuclear structure. Rutherford also experimented on radioactivity during 1899, he discovered two unique types of radiation which he named alpha and beta. These rays were well-known on the basis of penetrating power. Rutherford was honoured with a Noble prize in chemistry (1908).
Niels Bohr’s was mostly known his theory of the structure of the Atomic Model. Bohr’s mentor, Ernest Rutherford, had a theory that atoms were made up of a nucleus, with electrons scattering around it. However, Bohr made an important development on this theory, mainly about the electrons paths. He suggested that electrons continually travel in larger circle paths. He proposed that the outer paths could hold more electrons than the inner ones, and that the outer paths select the atom's chemical properties. It was because of his atomic model that Bohr was awarded a Nobel Prize in