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400
Democritus;
Lived in the ancient Greek times about 500 B.C. He believed that all matter was made of extremely small particles that could not be broken down or divided. The thought atoms in liquid were round and smooth, but the atoms in solids were roughand prickly. -
500
Aristole;
He didn't think there was a limit to the number of times matter could be divided. He thought there were four elements Earth, Air, Fire, Water. With four different qualities hot, cold, dry, and wet. -
John Dalon;
Dalton proposed the theory that all matter is made up of induvidual particles called, atoms which can be divided. -
Joseph John Tompson (J.J Thomas)
He believed that when materials are rubbed together they gain the ability tto attract or repel other materials. -
Hantaro Nagaoka
Believed atoms had a central nucules and the electrons move in small orbits like the rings surrounding Saturn. -
Ernest Rutherford
He believed that an atom has a dense and positively charged nuclues, with electrons that moved around randomly and freely in the space surrounding the nucleus. -
Niels Bohr
He believed that the electrons moved in circular orits at a fixed distance around the nuclues. -
Lewis de Broglie
Discovered the idea that particles in motion show properties of waves. Later scientest prove his theory correct. -
Erwin Schrodinger
He conducted a math problem to discribe the movement of electrons in atoms. -
James Chadwick
He proves the existence of neutrons . The Atomic nuclei has newtrons and positively charged protons.
