CHEMISTRY
2015-2016 SCHOOL YEAR
CLASSROOM: 510
EMAIL: bui@whsad.org
INSTRUCTOR: Ms. Bui
LAB ROOM: 506
ATOMIC MODEL TIMELINE
Name_______________________________________
Date: ______________________________________
Scientist
John Dalton
Model
Period: _____________________________________
Subject: Chemistry
Observation
Matter is conserved during a chemical reaction
Conclusion
Atoms are hard, indivisible
spheres of different sizes
J. J. Thomson
Cathode rays are deflected by magnetic/electric
fields
Atoms have small, negatively
charged particles as part of
their internal structure.
Ernest
Rutherford
Most alpha particles pass straight through gold
foil be a few are deflected
An atom is mostly empty
space with a small, dense,
positively charged nucleus
Neil Bohr
Unique spectral lines are emitted by excited
gaseous elements
Packets of energy are absorbed
or emitted by atoms when an
electron changes shells
Represents a sort of history of where the electron
has probably been and where it is likely to be
going. Imagine, as the electron moves it leaves a
trace of where it was. This collection of traces
quickly begins to resemble a cloud. The probable
locations of the electron predicted
by Schrödinger's equation happen to coincide with
the locations specified in Bohr's model
Atoms consist of orbitals,
regions of the most probable
electron location.
Planetary Model
Erwin
Schrodinger
Wave Mechanical
Model (Electron
Cloud Model)
Directions:
Using the Atomic Model Timeline and information on pages 1-2 of the textbook, create a timeline showing the following:
1. The name of the Atomic Model (make sure to put the model in the order of occurrence)
2. Draw a picture of the model (you may add color if so desired)
3. The name of the scientist associated with the model
4. A description of the model
1