Atomic Theory Notes

Democritus

Aristotle

Plato

Socrates

Matter is made up of earth, fire, air, and water.

Matter is composed of tiny, indestructible units called atoms.

Matter is continuous and can be divided infinitely.

Matter is made up of molecules only.

John Dalton

J.J. Thomson

Isaac Newton

Albert Einstein

Atoms of the same element are identical.

Atoms can be created or destroyed.

Atoms of different elements have different masses and properties.

Atoms of different elements can react and bond into chemical compounds.

The particles in the beam were negatively charged.

The particles in the beam were positively charged.

The particles in the beam were neutral.

The particles in the beam were heavy.

Negative electrons are embedded in a positively charged region.

Atoms are solid spheres like billiard balls.

Atoms have a nucleus at the center.

Electrons orbit the nucleus in fixed paths.

To discover electrons

To test the Thomson model of the atom

To create gold atoms

To measure the mass of alpha particles

Most alpha particles passed straight through the gold foil.

All alpha particles were absorbed by the gold foil.

Some alpha particles were deflected at large angles.

The experiment showed that atoms have a dense nucleus.

Niels Bohr

James Chadwick

Erwin Schrödinger

Albert Einstein

Energy levels

Electron clouds

Proton zones

Neutron shells

It updated the electrons of the Bohr model.

It describes the area where electrons are likely located.

It was proposed by Erwin Schrödinger.

It states that electrons orbit the nucleus in fixed paths.