Chemistry Oct. 9 & 12, 2015

•OBJECTIVE: Students will describe orally and in writing how the model of the atom has changed from 400 BC to today.

•W.O.D. Ruddy-having a healthy, reddish color

•WARM-UP

1.Democritus was the first individual credited with the idea that matter might be composed of atoms. Describe his proposed model of the atom.

2.What was the problem with Democritus’ idea of the atom?

CW

•Describe the model of the atom proposed by each of the following scientists and show how each model is different from the previous model:

•John Dalton

•J.J. Thomson

•James Chadwick

•Ernest Rutherford

•Niels Bohr