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7900 BCE
Discovery of copper
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5000 BCE
discovery of gold,lead,silver and iron
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500 BCE
Democritus named the atom and thought it had spikes, hooks, and ball and socket joints.
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John Dalton invented the idea of the scientific model
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J.J Thompson discovered electrons and found out that atoms have a positively charged part and a negatively charged part.
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Henry Becquerel and Pierre and Marie Curie discovered radioactivity.
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Dmitri Mendeleev developed the periodic table.
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Ernest Rutherford discovered that the positive charge comes from a tiny nucleus with neutrons in the center of the atom and electrons surround the nucleus.
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Niels Bohr discovered the electron shell.