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7 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Democritus’s atom |
If you keep cutting a substance in half repeatedly, there will eventually be a point where you can’t cut anymore |
First thought of an atom |
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Dalton’s atom |
Everything is made up of atoms (small indestructible spheres) and different elements have unique atoms |
Plane sphere model with no sub-atomic particles |
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JJ Thompson’s atom |
Thought up the plum-pudding model which consists of a weakly positive sphere of mass and negative electrons throughout |
First theory to have sub-atomic particles |
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Rutherford’s atom |
Atoms are made up of a positively charged nucleus orbited by negatively charged electrons |
Rutherford’s model is closest to that used today |
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Bohr’s suggestion |
Electrons can only exist in specific orbits (energy levels) around the nucleus, he named these, electron shells |
Specific distances electrons can be from the nucleus |
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Current model |
Positively charged nucleus made of specific numbers of protons and neutrons orbited by negatively charged electrons |
3 sub-atomic structures |
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Relative masses of sub-atomic particles |
Proton - 1 Neutron - 1 Electron - negligible |
Arbitrary units |
