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Aristotle
Aristotle lived in ancient greek times about 100 years after Democritus. He thought that particles (atoms) could be divided an infinate amount of times. his atomic modle involved the four elements. Discovered this throught the work of discourse. -
John Dalton
John Dalton was born in 1776 . He believed that all elements are composed of atoms ,and that all atoms of the same element have the same mass and atoms of a different element also have different masses. Dalton also beleived that compounds are made of two elements and have a fixed compisition. sphereicle model
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Joseph John Thomson
In 1904 Thomson suggested a model of the atom as a sphere of positive matter in which electrons are positioned by electrostatic forces. He hypothesized that particles came from inside the atom.Thomsons experiments were the first evidence of smaller particles within the atom.his experiments used a device that in the center of it there is a sealed glass tube with a metal disk at each end the disks are charged 1 + the other - -
hantaro nagaoka
Hanataro beileived that an atom has a cenrtal nucleus and electrons move in orbit like rings around Saturn. He discovered this through the work of others -
Ernist Rutherford
in 1899 he dicovered uranium emits fast moving particles that have a positive charge and named them alpha particles.in 1909 he asked one of his students to see what would happen if aphal particles pass through gold.his student designed and teted the Gold Foil Experiment. After running the experiment Rutherford dicoved the nucleus. -
Ernest Marsden
Marsden helped Rutherford in the discovery of the nucleus and the making of Rutherfords atomic model and the Gold Foil Experiment -
Niels Bhor
Bhor agreed with rutherford's model of nuecleus surrounded by a large volume of space but bhor's model focused on electrons. Bhor beilieved that electrons move in sphereicle orbit at a fixed distance away. -
louis de broglie
He beleived that particles moved in a waves wich is defined by the Schrodinger equation, which is purely mathematical. he also used the work of Albert Eienstien and John Plank. -
Erwin Schodinger
He contributed by writing the Schrodinger equationand and through this he dicovered a hydrogen like atom. He used the equationn to describe the motion of electrons. His model was the electron cloud model -
James Chadwick
He discovered unknown particles in the atomic nucleus wich he named neutron due to it lack of electric charge.He discovered this by smashing alpha particles into beryllium, a rare metallic element, and allowed the radiation that was released to hit another target: paraffin wax. When the beryllium radiation hit hydrogen atoms in the wax, the atoms were sent into a detecting chamber. -
Democritus
Democritus live in acient greece in about 500 BC. Democritus believed that all matter consisted of extremely small particles that could not be divided . He named those very particles atoms. he also believed that atoms differ between phases. He discovered this through the work of discourse
