Development of the atom

Created by: leah.cm
Created on: 14-02-23 15:41

First

Atoms were thought to be tiny balls that cannot be divided

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J.J. Thompson

Discovery of the electron
- Plum pudding model
- atom is a ball of positive charge with
negative electrons embedded in it

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Alpha Particle Scattering Experiment

conclusion that the mass of an atom was
concentrated at the centre (nucleus) and that the nucleus was charged

● A beam of alpha particles was aimed at very thin gold foil
● Some of the alpha particles emerged from the foil at different angles, and some even came straight back
● the positively charged alpha particles were being repelled and deflected by a small c

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Neil Bohr

suggested electrons orbit the nucleus at specific distances

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Later experiments

positive charge of any nucleus could be subdivided into a whole number of smaller particles, each particle having the same amount of positive charge

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James Chadwick

provided the evidence to show the existence of neutrons within the nucleus

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Other cards in this set

Card 2

Front

Discovery of the electron
- Plum pudding model
- atom is a ball of positive charge with
negative electrons embedded in it

Back

J.J. Thompson

Card 3

Front

Back

Card 4

Front

suggested electrons orbit the nucleus at specific distances

Back

Card 5

Front

positive charge of any nucleus could be subdivided into a whole number of smaller particles, each particle having the same amount of positive charge

Back

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Development of the atom