Atomic Models
Experiments Behind Atomic Models
100

He proposed the first idea of the atom around 400 BCE.

Democritus

100

This device helped J.J. Thomson discover the electron.

Cathode Ray Tube

200

He discovered the electron using a cathode ray tube.

J.J Thompson

200

J.J. Thomson’s experiment showed that atoms contain these.

Electrons

300

This model looked like a 'plum pudding' with electrons scattered inside.

Thompson Model

300

In Rutherford’s gold foil experiment, these were fired at a thin sheet of gold.

Alpha Particles

400

He discovered the nucleus by shooting alpha particles at gold foil.

Ernest Rutherford

400

Rutherford's surprising result: some alpha particles did this when they hit the foil.

Bounced back/reflected

500

This scientist proposed that electrons orbit the nucleus in fixed energy levels.

Bohr

500

Millikan used this experiment to calculate the charge of a single electron.

Oil Drop experiment

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