Atomic Model Timeline Project
Objective: Understand the experimental design and conclusions used in the development of the modern
atomic theory, including Dalton's postulates, Thompson's discovery of the electron properties, Rutherford's
nuclear atom, and Bohr's nuclear atom.
Atomic Model Timeline Project
1. Be chronological in its sequence, with the dates clearly shown (it need not be to scale).
2. Contain, through pictures and/or explanations the significant contributions and experiments of
those scientists and atomic models listed above.
3. Be neat and legible.
Your timeline is due on ____________________
You do not have to follow the typical horizontal timeline format; you may be creative and use any format you
wish.
Introduction:
If you were asked to draw the structure of an atom, what would you draw? Throughout history scientists have
accepted five atomic models. Our perception of the atom has changed from the early Greek model because of
clues or evidences that have been gathered through scientific experiments. As more evidence was gathered old
models were discarded or improved upon. Your goal is to trace the atomic theory through history.
Task:
You will use your notes, worksheets and the Internet sources provided to learn more about the scientists and
discoveries that have led to our current knowledge of the structure of the atom.
Using your research, construct a timeline as a visual representation of the development of modern atomic
theory.
Draw the five historical models of the atom - Democritus, Thomson's Plum Pudding, Rutherford, Bohr, Modern
Electron Cloud
Process:
_ Read the whole direction.
_ Get out your notes from the atomic theory ppt.
_ Use any of the following Web sites to get information about listed scientists and their discoveries that were
not in your notes. You may search other Web sites on your own or use library resources.
Organize the following information on the Timeline:
_ Names of all 9 scientists in the table below
_ The year of the scientists discovery
_ In 1-2 sentences tell the importance of the discovery that relates to the structure of the atom (some of these
people did many types of research)
_ Pictures of the five historical models of the atom – Dalton,
Thomson's Plum Pudding, Rutherford, Bohr, Modern Electron
John Dalton
James Chadwick
Ernest Rutherford
J.J. Thomson
Democritus
Robert Millikan
Neils Bohr
Max Planck
Erwin Schrodinger
A timeline is in chronological order – earliest time to latest time. Because you are going to keep your comments
to 1-2 sentences, a graph or report will not be appropriate.
Conclusion:
This assignment is based on 100 points. You can earn extra points by making models to display in the
classroom or making a large timeline with pictures of the scientists. This assignment will allow you to observed
how the Atomic Theory started as a philosophical idea and through quantitative experimentation, has been
developed to include the current Electron Cloud Model. You will see that as scientists discovered more and
more information they discarded parts of older theories to design an atomic model that provided a more
accurate representation of the atom. It is important for scientists to challenge current theories and modify them
as more knowledge becomes available. Your research provides you with a historical perspective of our
knowledge of the atom's structure.
Evaluation:
Category
4
3
Dates/Scientist
All scientists
listed dates are
correct and in
order.
6-8 scientists are 4-6 scientists are 1-3 scientists are 0 scientist are
list or 2 are out of listed or 3-5 are listed or 6-7 are listed or all are
order
out of order
out or order
out of order
Contribution to
Atomic Theory
All contributions
listed and apply
to the Atomic
Theory
2-3 errors or
contributions not
listed or do not
apply to the
Atomic Theory
Models of Atoms
All 5 models are 4 models are
3 models are
2 or 1 models are 0 models are
drawn correctly drawn correctly drawn correctly drawn correctly drawn correctly
and named
and named
and named
and named
and named
Timeline and
Timeline and
Timeline and
Timeline and
Timeline and
models are
models are
models are
models are messy models are not
exceptionally
attractive in terms acceptable in
with no use of
legible, messy
attractive in terms of layout,
terms of neatness, color.
and have no
of layout,
neatness, and use layout but no use
color.
neatness, and use of color
of color
of color.
Attractiveness
2
4-6 errors or
contributions not
listed or do not
apply to the
Atomic Theory
1
7-8 errors or
contributions not
listed or do not
apply to the
Atomic Theory
0
9 or more errors
or contributions
not listed or do
not apply to the
Atomic Theory