Atom History

Democritus

Democritus's Theory

• Atoms are in every single thing
• Atomos- uncuttable or indivisible

John Dalton

John Dalton's Theory

• Substances are made up of atoms
• Atoms of the same element look exactly alike
• Atoms of a different element look different
• Atoms join other atoms to make new sunstances

J.J. Thomson

J.J. Thomson's Theory

• Positively charged plate attracts a beam and makes it bend down
• Called the The Plum Pudding Model

Ernest Rutherford

Ernest Rutherford's Theory

• Discovered the nucleus
• Everything floats around the nucleus

Niels Bohr

Niels Bohr's Theory

• Electrons move around the nucleus in a path
• Electrons can jump from one path in one level to another level

Electron Cloud

Electron Cloud Theory

• Created by Schrodinger and  Heisenberg in 1925
• The exact path of an electron can't be found like Bohr's theory suggested
• There are regions where electrons are likely to be found