Unit 3.1 - The Atom

Greek Scientist

Small, hard, indivisible spheres

Coined term "Atomos"

Means "Uncuttable"

Came up with first workable model

Indestructible, hard spheres

Took Chadwick's electron and proposed idea of positive particle

Model called the "Plum Pudding Model" or the "Chocolate Chip Cookie Model"

Negative Electrons surrounded by a "soup of positive particles"

Gold Foil Experiment

Proved the existence of the Proton

Discovered that the Nucleus was TINY

Electrons going around the nucleus like planets around the sun

HUGE amount of empty space between Electrons and Nucleus

Discovered that Electrons exist in set levels called "Electron Shells"

Each level can only hold a specific amount of Electrons

Each row on the Periodic Table is a new Electron Shell

Came up with the idea that Electrons exist in clouds

Quantum Mechanics = math problems that can be used to predict an Electron's location at 90% accuracy