Ch. 4/5 Notes Day 1 1/25/16

Objectives SWBAT explain the progression of the atomic model SWBAT identify key scientists and their contribution to the atomic model Students will develop pneumonic devices to remember scientists and the model they developed

Here’s how to setup your notes (use a full page) Scientist Year Experiment and/or Hypothesis Atomic Model Pneumonic Device 3 rows

Democritus Pneumonic Device Democritus’ Atomos No Slice 440 BC (2,500 years ago) Hypothesis ALL matter is made of particles too small to be seen, that cannot be split into smaller parts “Atomos” meaning “cannot be cut” Atomic Model Sugar is made of “sugar atomos” Rocks are made of “rock atomos” Copper is made of “copper atomos”

John Dalton 1803 Experiment Hypothesis Measured masses of elements and compounds during chemical reactions Hypothesis All elements are made of atoms All atoms of the same element are IDENTICAL Compounds contain atoms of more than one element The same compounds always combine the same way

Dalton’s Atomic Model Tiny, solid, indestructible particles “Bowling Ball Theory” Pneumonic Device Dalton’s Atomic Bowling Balls Solid Compounds And Bowling Balls Of John Dalton

J.J. Thomson 1897 Experiment Hypothesis Shot lasers between two magnets ( + & -). Laser bent towards the positive magnet. Hypothesis Atoms made of smaller particles Atoms have a neutral charge Atoms are positively charged “blob” of matter, with little negative charges scattered throughout.

J.J. Thomson’s Atomic Model Tiny solid sphere (like Dalton) but with negative charges scattered throughout “Plum Pudding” Think of mint-chocolate chip ice cream Pneumonic Device Thomson’s Unique Plum Pudding And Charges

Ch. 4/5 Notes Day 2 1/26/16

Objectives SWBAT explain the progression of the atomic model SWBAT identify key scientists and their contribution to the atomic model Students will develop pneumonic devices to remember scientists and the model they developed

Here’s how to setup your notes (use a full page) Scientist Year Experiment and/or Hypothesis Atomic Model Pneumonic Device 3 rows

Ernest Rutheford 1911 Experiment Hypothesis Shot alpha particles (+ charge) at gold foil. The particles bounced off in crazy (unpredicted) directions Hypothesis Atoms have very small, positively charged nucleus Nucleus surrounded by negative charges orbiting nucleus Atoms are mostly empty space

Rutheford’s Atomic Model “Planetary Model” Negatively charged electrons orbit positively charged nucleus Mostly empty space Pneumonic Device

Neils Bohr 1913 Experiment Hypothesis None! Just a super smart dude. Electrons orbit the nucleus at fixed distances. Each distance is an energy level. Electrons gain or lose energy as they move between energy levels.

- - - - - - - Bohr’s Atomic Model “Bohr Model” Most commonly used in chemistry and chemistry classes Pneumonic Device - - - - - -

Erwin Schrödinger 1926 Experiment Hypothesis None! Just a super smart dude. Famous for Schrödinger’s cat theory. Hypothesis Electrons orbit the nucleus in a sort of “cloud” “Cloud” describes where electrons probably are

Schrödinger’s Atomic Model “Electron Cloud Model” Most accurate model of the atom Difficult to use for science problems Pneumonic Device