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Law of Constant Composition
The Law of Constant Composition was formulated by Joseph Proust. This law states that if a compound is broken down into its constituent elements, the masses of the constituents will always have the same proportions, regardless of the quantity or source of the original substance. -
Law of Conservation of Matter
The law of conservation of matter was formulated by Antoine Lavoisier. The law means that mass is conserved. His experiment proved that the original object has the same mass as the produced mass. -
Law of Multiple Proportions
The law of multiple proportions was created by John Dalton. The law states that if two elements form more than one compound between them, the masses of one element combined with a fixed mass of the second element form in ratios of small integers. -
Atomic Theory
The atomic theory was proposed by the scientist John Dalton. This theory states that everything is made up of atoms we just cannot see them. -
Electrons
Cathode ray tubes were created by Michael Faraday. These tubes were used to see cathode rays that are found in all atoms. It was not until later when JJ Thompson gave them the name electrons. -
The Plum Pudding Model
Shortly after J.J Thompson discovered the electron. It was in reference to the dessert of plum pudding because it states that electrons float in a positively charged material. -
Protons
Ernest Rutherford used the idea of the plum pudding model to discover protons. He used his gold foil experiment to see large deflections in alpha particles. He did a discovery with a nuclear atom model where there is a very small area called the nucleus and he put alpha particles against nitrogen atoms and protons were released. -
Neutrons
James Chadwick discovered neutrons. He discovered this through a new type of radiation that contained neutral particles. He discovered that these neutral atoms come from the nucleus. This discovery completed the atomic model.