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Period: 460 to 370
Democritus
He thought that the atom is the smallest particle and could not go any further. He discovered this in 420 BC -
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Atonie Lavoisier
He proposed that an element should be defined as a substance that cannot be broken down into any simpler substances. He proposed this in 1768 -
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Joseph Proust
According to this law developed by Joseph Proust in 1799, substances always combine in the same proportions. -
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John Dalton
He discovered that all matter must be made of seperate particles -
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Robert Bunsen
Discovered the bunsen burner and found out that each element had its on unique colour band. he discovered this in 1860 -
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Dimitri Mendelev
The father of the periodic table because he was known for devising the table that had 62 known elements at the time in order.he discorvered this in 1869 -
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JJ Thompson
Was the creator of the plum pudding model. JJ was very important because he found out that atoms consisted of negative charges. -
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Ernest ruthford
Ernest wanted to find out what was inside the atom, he did this by making the Ruthford model in 1911 and it showed that some atoms would pass a gold sheet and some would deflect. -
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James Chadwick
Discovered the neutrons and that neutrons have no charge and weigh the same as protons.