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Democritus
Democritus theorized that matter can’t be divided forever. Once you can’t divide the matter anymore and it becomes indivisible is now an atom. His idea of the atom was a simple, solid sphere that makes up everything. He was the first to theorize about atoms. No one believed democritus and totally disregarded his theory, unitl the 1800s. -
Robert Boyle
Boyle's Law: pressure and volume of a gas have an inverse relationship, when temperature is held constant. If volume increases, then pressure decreases and vice versa, when temperature is held constant. -
Antoine Lavoiser
Lavoiser is famous for the Law of Conservation. After careful studying he concluded that the law states that matter cannot be made or destroyed. With this came the beginning of modern chemistry. -
John Dalton
After much research, John Dalton concluded four rules for the atom.
1) All matter is made of atoms. Atoms are indivisible and indestructible.
2) All atoms of a given element are identical in mass and properties
3) Compounds are formed by a combination of two or more different kinds of atoms.
4) A chemical reaction is a rearrangement of atoms. -
Robert Millikan:
Millikan had discovered the charge of an electron and the mass of an electron by using his famous oil drop experiment. -
Dmitri Mendeleev
He arranged elements into 7 groups with each group having similar properties. -
Ernest Rutherford
Rutherford is known as the "Father of Physics". He is quite well known for his Gold Foil Experiment, which porved that atoms have a nucleus, that the nucleus makes up a very small portion of the atom, and that electrons orbit the nucleus at a great distance. -
Eugen Goldstein
He used crt to study canal rays which had opposite magnetic and electrical properties of an electron. -
J.J Thompson
J.J. Thomson's contribtuions were huge in the world of the atom. Thanks to his invention of the Cathode Ray, he discovered the sub-atomic particle, the electron. He also discovered that the atom is divisible, and that atoms have a postive charge. Another very well-known contribution of his was the Plum Pudding model, used to show that atoms are made of positve and negative charged atoms. -
Niels Bohr
Bohr had a few contributions to the evolution of the atom. He stated that electrons can jump from paths or levels around the nucleus. He also founded that electrons on the outer shell determine the element's chemical properties, and that electrons only travel at certain distances from the nucleus. -
Henry Mosely
Mosely had founded the atomic number by proving an inverse relationship between the wavelength and frequency of elements on the periodic table. With that he also could find the number of electrons in a single element, and discovered that with every electron in an element there has to be an equal amount of proteins. -
Henry Moseley
Founded the atomic number by proving an inverse relationship between the wavelength and frequency of elements on the periodic table. with that also could find the number of electrons in a single element. also founded with every electron in an element there has to be an equal amount of proteins. -
Max Plank
Quatum Theory: Energy is made of indicidual units; or quanta -
Erwin Schrodinger
He combined the equations for the behavior of waves with the de Broglie equation to generate a mathematical model for the distribution of electrons in an atom. -
James Chadwick
James Chadwick discovered the neutron. With the neutron, he noted that it has no charge but has a mass almost equal to that of the proton. With this new era of nuclear science thanks to his discovery, he later studied civilian and military applicatoins of the neutron.
