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Aristot
He thought that there was no limit on how many times a atom can be divided. He came up with a model that had Hot, Dry, Wet, and Cold elements. Inside of the graph he put Fire, Earth, Water, and Wet. Fire is between hot and dry. Water is between cold and wet. -
Isaac Newton
Issac theorized a mechanical universe with small, solid masses in motion. -
John Dalton
He pictured atoms as tiny, indistructible particles, with no internal structure. Dalton had a large interest in predicting weather so while doing that he studied the behavior of gases in air.
Dalton proposed the theory that all matter is made up of individual particles called atoms, which can not be divided.
He gathered evidence for the existence of attoms by measuring the masses of elements that combine when compounds are formed. -
Joseph Proust
He discovered that a given compound always has the same elements in the same proportion by mass. -
J.J. Thomson
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Erwin Scrondinger
Schrodinger took the ideas from de Broglie and other scientists and put them together in a single equation that is named after him, The Schrodinger Equation. This equation became public in 1926. This equation is still used today to understand atoms and molecules. His work lead to the electron cloud model. -
Ernest Marsden
In 1909 Ernest Marsden was instructed by Ernest Rutherford to see what happens to alpha particles when they pass through a thin sheet of gold. Because of the fact that they worked together, Mr. Rutherford and Marsden have the same model and theory. -
Hantaro Nagaoka
Suggest that an atom has a central nucleus.His model was based around an analogy of the stability of the rings around Saturn. -
Ernest Rutherford
Rutherford publishes his atomic theory model as having a central positive nucleus surrounded by negative orbiting electrons. He used J.J. Thomson's theory and made his own model. He done this by have a peice of gold foil, a laiser, and a detecting screen. -
Niels Bohr
He agreed with Rutherford's model but focused on the electrons. In niels Bohr's model, the electrons move in spherical orbits at fixed distances form the nucleus -
Louis de Broglie
He discovered that moving produts like elctrons having some properties of waves. He did this by working out math problems. -
Werner Heisenberg
Heisenberg worked out that particles had a lot more energy over short distances than expected. He realized that a particle can borrow energy as long as it is paid back in a short time. -
Democritus
He believed that matter is consisted of extremely small particles that could not be devided. He called these particles "atoms" from the Greek word "atomos", which means "uncut" or "indivisible" . He believed that there were many types of atoms with specific features for example the ones in liquids were smooth and round, and the one's in solids were rough and prickly. -
James Chadwick
He confirms the existence of neutrons which have no charge. He did this bybombarded the alpha rays on Beryllium atom and observed that Beryllium artificially became radioactive for a short time
