Lesson/Unit Title:
Submitted by:
District and School:
Grade Level:
History of the Atomic Theory; A Dear John Letter
Tim Watters. (Science Teacher)
Middletown (RI) Public Schools.
Middletown High School
10-12
Lesson or Unit
Plan:
Lesson Plan
Content Area:
Chemistry
Time Allotment:
Academic
Standards/
Common Core of
Learning:
4-5 class periods.
New Standards Performance Standards:
Physical Science Concepts S1a: The student produces evidence that
demonstrates understanding of structure of atoms.
Scientific Thinking S5f: The student works individually and in teams
to collect and share information and ideas.
Scientific Communication S7d: The student explains a scientific
concept or procedure to other students.
Abstract:
Goal
Chemistry students work in small groups to research one of the
following models of atomic structure: John Dalton’s solid sphere
model, J.J. Thomson’s plum pudding model, Ernest Rutherford’s
nuclear model, Niels Bohr’s planetary model, and the wavemechanical model. Each group prepares a one page handout for all
classmates summarizing the model and the evidence that led to it.
Each student then uses the handouts as a resource to write a personal
letter to John Dalton explaining the advances to his atomic theory.
The goal of the lesson is to develop an understanding of the history of
the atomic theory, particularly the notion that our understanding of
atomic structure changes depending on available evidence. The
opportunity to work collaboratively on a common task that peers will
depend on is also important.
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Performance
Indicators:
Students will demonstrate an understanding of atomic structure by
explaining it in their own words and representing it with diagrams
(S1a)
The student works individually and in teams to collect and share
information and ideas. (S5f)
The student clearly explains a scientific concept to other students
using appropriate media. (s7d)
Materials:
Technology:
A variety of chemistry textbooks and encyclopedias.
Computer technology with software capable of generating a one page
handout (Word processor or publishing software) helps but is not
necessary.
Internet access helps but is not necessary.
Instructional
Procedure:
Introduction:
Focus Questions
What are atoms?
How has our understanding of atomic structure changed?
Why I Think This Is Important
It's not hard to find examples of technology changing the way we
think about the world. Anton van Leeuwenhoek's microscope of the
late 1600's immediately comes to mind. Seeing a microcosm of life in
a drop of pond water had a profound effect on most people lucky
enough to witness it. Electricity, X-rays, radioactivity, high speed
photography, scanning tunneling microscopes, and other technologies
have allowed us to investigate the world in ways unimaginable to our
ancestors. What we have learned has forever changed the way we
view the world.
Advances in our understanding of the nature of atoms have clearly
depended on technology. Electrons, for example, could not have been
discovered without electricity. Technology along with creative people
passionate about learning has led us to our current view of the atomic
world. Knowing a little something about atoms and how our
understanding of them has changed during the past few hundred years
are worth the effort. Heck, if we can understand something we can't
even see, maybe there's hope we can understand even crazier things in
our world.
Objectives
This activity will provide you with an opportunity to see how
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technology has shaped our view of atomic structure and learn some of
the details about the history of the atomic theory as well as the
structure of atoms.
Activities:
You will be assigned to a group of three or four students.
Your group will be assigned to research a single aspect of the atomic
theory.
John Dalton's solid sphere model
J.J. Thomson's plum pudding model
Ernest Rutherford's nuclear model
Niels Bohr's planetary model
Quantum-mechanical model
Your group will present your findings to the entire class and pass out a
one-page handout summarizing your information. This handout will
be the primary resource for your classmates.
Who — Person(s) responsible.
What — A description and an illustration of the model.
Where — Country, state, university, etc.
When — Date(s).
Why — The prior knowledge at the time.
How — A summary of the technology or evidence used to
develop the model.
References — Page numbers from our textbook and at least
two other helpful resources.
Closure:
Working alone, you will use the information presented by all the
groups to write a personal letter to John Dalton summarizing the
history of the atomic theory.
Dear John...
Summarize each of the five models in chronological order.
Include an illustration of each model.
Briefly describe the technology or experimental evidence used
to develop each model.
Predict the next breakthrough in our understanding of atomic
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structure.
Assessment:
Class Handout
Includes who, what, where, when, why, how, and references on one page.
Information is accurate and helpful.
Layout is attractive and promotes understanding.
Letter to John Dalton
Scored according to the school-wide holistic writing rubric
Summarizes the history of the atomic theory from John Dalton to the quantummechanical model.
Includes a brief description of the experimental evidence for each model.
Information is accurate.
Accommodations
and Modifications:
Opportunities to accommodate diverse learning styles occur in the
group work leading up to presenting the summary to the entire class.
Possibilities include demonstrating 3-dimension models, multimedia
presentations, skits, songs, etc. Also, the final product — a letter to
John Dalton — may be modified to include an oral recording, video,
etc.
Extensions:
Extensions include the possibilities to perform or demonstrate
historical experiments that provided supporting evidence for advances
of the atomic theory. Having students dress in period costumes when
presenting to the class or putting together a web page on the history of
the atomic theory also provides easy extensions of the lesson.
Putting more emphasis on the oral presentation aspect of this lesson
provides opportunities to address communication skills.
Reflection:
The lesson works well. The jigsaw method of presenting atomic theory
makes a traditional teacher centered lesson more student centered.
Students have provided mostly positive feedback about this lesson.
Connection to
Other Content
Areas:
Connections can easily be made to History. Having students what else
was occurring in the world at the time of the developments in atomic
theory can provide rich opportunities for History classes. Also, having
students describe the technology available at the time the atomic
models were being developed (Was electricity available?
Radioactivity? Etc.) provides connections to the general topic of the
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impact of science on society.
Business and
Community
Partners
None
Acknowledgements,
Funding Sources:
None
Contact
Information:
Author’s email address is twatters@mpsri.net
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