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Democritus
He came up with the theory that everything is made up of smaller things that he called "atoms" -
John Dalton
john Dalton theory was that all matter is made of atoms, and that they are all indivisible and indestructable. Also, every ayom of a given element have the same mass and properties. compounds are made up of two or more different kinds of atoms. and finally, a chemical reaction is a rearangement of the atoms. -
Antoine Lavoisier
Antoine came up with the first virsion of the law of conservation of mass, he also named some of the elements like oxygen and hydrogen. he also helped construct the metric system. -
Joseph louis proust
Proust came up with the idea that chemical substances combine to make a small number of compounds. -
Michael Faraday
He came up with the idea that atoms have an electrical component -
henri becquerel
While studying the effect of x-rays on photographic film, he discovered some chemicals spontaneously decompose and give off very pentrating rays. -
Joseph John Thomson
JJ thomson discovered the Electron, And created a model for what the atoms might look like. -
Robert Andrews Milikan
Robert Milikan created a method that allowed scientists to measure the charge of an electron -
Ernest Ritherford
Ernest was responsible for dicsovering Alpha and Beta Rays. this set forth the law of radioactive decay. his most important discovery was the dicovery of the nuclear structure of the atom -
albert einstein
Albert was the first man to prove the existence of atoms using only a microscope! -
Niels Bohr
Niels invented the nuclear drop theory, the theory that a liquid drop provides an accurate representaion of an atoms nucleus. -
Erwin Schrodinger
Erwin schrodinger took the bohr model a few steps forward by using equations to measure the likelehood of finding an electron in a certain position. -
louis de Brogile
he invented the Wave Mechanics theory. this theory improves our knowledge of the physical nature on the atomic scale. he won a nobel prize for physics on his wve nature of electrons dicovery in 1929 -
Max Planck
Planck is known as the originator of the Quantum Theory of energy. his work contributed to understanding the atomic and subatomic proccesses. -
Glen T. Seaborg
Seaborg is responsible for dicovering and identifying nine Transuranium elements numbers 94 through 102 -
James Chadwick
Until 1932, the atom was believed to be composed of a positively charged nucleus surrounded by negatively charged electrons. In 1932, James Chadwick bombarded beryllium atoms with alpha particles. An unknown radiation was produced. Chadwick interpreted this radiation as being composed of particles with a neutral electrical charge and the approximate mass of a proton. This particle became known as the neutron. With the discovery of the neutron, an adequate model of the atom became available to ch -
Marie & Pierre Curie
Pierre and Marie Curie are best known for their pioneering work in the study of radioactivity, which led to their discovery in 1898 of the elements radium and polonium. -
Aristotle
Aristotle believed that everything was made from the four elements, Fire, Water,earth, and air.