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400
Democritus
Atoms are indestructible. Atoms are solid but invisible.Atoms are homogenous.Atoms differ in size, shape, mass, position, and arrangement. -
440
Empedocles
Thought the world was made up for main elements Earth, Fire, Water, Air -
Feb 3, 1450
Renessance
Florence becomes the center for renessance art and learning -
America
America is ofically a country -
Jon Dalton
Proposed that all matter is composed of very small things which he called atoms. When Dalton proposed his model electrons and the nucleus were unknown. -
Abraham
Abraham lincon is born -
The war of 1812
a military conflict, lasting for two-and-a-half years, between the United States of America and the United Kingdom of Great Britain -
Abraham
Abraham lincon is assinated -
J.J. Thomson
Determined that all matter is made up of tiny particles that are much smaller than atoms. He originally called these particles 'corpuscles,' although they are now called electrons. This discovery upended the prevailing theory that the atom was the smallest fundamental unit. -
Australia
Australia Becomes a Commonwealth -
Ernest Rutherford
Overturned Thomson's model he demonstrated that the atom has a tiny, nucleus. -
Chinese Revolt
On October 10th, a revolution broke out against the Manchu government. The government was in such disarray and central power was so limited -
Niels Bohr
Niels Bohr proposed a theory for the hydrogen atom based on quantum theory that energy is transferred only in certain well defined quantities. -
Louis de Broglie
He believed that electrons can act like both particles and waves, just like light. He also said that waves produced by electrons contained in the orbit around the nucleus -
James Chadwick
Discovered the nuetron and he found that electrically charged plates and magnets deflected a cathode ray -
Nelson Mandels
Nelson Mandela became the first black president of South Africa -
Credit Card
First modern Credit card introduced