A Tale of Four Electrons
Using creative writing to
learn about chemical bonding
Paul Burgmayer
ne sweltering summer afternoon,
four electrons sat on a river
bank, restless and with nothing
to do. On the left was Crystal,
a sodium electron. Crystal [was] often…
lonely because she was the only electron in
her atom’s outer shell.
“Once upon a time, in a land far, far away…”
began the chemistry teacher, “each of these
electrons began in single atoms. Eventually,
they bonded with other atoms, following one
of three fates: ionic, covalent, or metallic
bonding to form chemical bonds…Bonding
is a sort of rite of passage that changed the
lives of these electrons forever.”
Here ye, here ye to all who dare:
The King of Periodicity henceforth
proclaims his desire for four brave and
noble electron knights to join the famed
“Knights of the Periodic Table.” Those
electrons of atoms of noble birth will
face challenges unlike any other.
“And in the news today, Bonding, Inc.,
is looking for new electrons to begin
careers for the large bonding firm.
Electrons interested…”
Mike’s mother interrupted the news
report: “Mike, do you want to eat? We have
Proton Pebbles, Fluorine Flakes, and—”
“Not now! They’re talking about the
new jobs!” Mike turned up the TV.
February 2011
53
So begin four student essays for “A Tale of Four Electrons,”
a creative writing assignment I use with my 10th-grade Honors Chemistry students. The project helps students consolidate their learning about bonding—an important unifying
theme in chemistry—and answer questions such as
How are ionic, metallic, and covalent bonds related?
How do variations in electron configuration across a period alter expected bonding? and
How do intermolecular forces depend on bond polarity?
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words (Figure 2) in ways that demonstrate their understanding. (Students are also given the option to create a multipage,
hyperlinked PowerPoint to explain chemical bonding, but the
story option is encouraged.)
To simplify the grading process, I provide students with
a story line consisting of four parts (Figure 3, p. 56):
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I have found that most students are enthusiastic about this
assignment. I am also amazed by their ability to intertwine
creative stories with bonding concepts and vocabulary words.
This article describes the assignment, and the processes I use
to grade students’ tales.
The assignment
I begin by giving students a copy of the assignment and a grading sheet (see “On the web”). Students must incorporate all 14
bonding concepts (Figure 1) and 35 of 44 bonding vocabulary
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In Part 1, students describe the “life” of each electron in
an unbonded atom, including a name, a description of
the atom, and the orbital configuration.
In Part 2, they must form one of the four bonds (i.e.,
ionic, metallic, polar covalent, or pure molecular/
network covalent) with an appropriate atom and describe the electron’s bonding experience.
In Part 3, students explain the bonding results on a molecular and everyday level, including expected physical
properties and any intermolecular forces that arise. This
dual view of the world (particulate vs. macroscopic) is a
major theme throughout my course and an important
part of the National Science Education Standards (NRC
1996; Content Standard B).
Figure 1
Bonding concepts.
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Most atoms are chemically bonded to other atoms.
The three major types of chemical bonding are ionic,
covalent, and metallic.
In general, atoms of metals bond ionically with atoms of nonmetals, atoms of metals bond metallically with each other, and atoms of nonmetals bond
covalently with each other.
Atoms in molecules are joined by covalent bonds.
The bond length between two atoms in a molecule
is the distance at which the potential energy of the
bonded atoms is minimized.
The octet rule states that many chemical compounds
tend to form bonds so that each atom—by gaining,
losing, or sharing electrons—shares or has eight electrons in its highest occupied energy level.
A single bond is a covalent bond in which a pair of
electrons is shared between two atoms. Covalent
bonds with more than one pair of shared electrons
are called multiple bonds.
Bonding within many molecules and ions can be indicated by a Lewis structure (or what is sometimes
called an electron dot diagram). The Lewis structure
for water, for example, looks like this:
The Science Teacher
Molecules or ions that cannot be correctly represented by a single Lewis structure are represented by
resonance structures.
uu An ionic compound is a three-dimensional network
of positive and negative ions mutually attracted to
one another.
uu Because of the strong attraction between positive and negative ions, ionic compounds tend to
be harder and more brittle and have higher boiling
points than materials containing only covalently
bonded atoms.
uu Polyatomic ions are charged groups of atoms held
together by covalent bonds.
uu Metallic bonding is a type of chemical bonding that
results from the attraction between metal atoms
and mobile electrons floating in a conduction band
between metal atoms.
uu In metallic bonding, the lack of a band gap between
valence and conduction bands gives metals their
properties of high electrical conductivity, malleability, ductility, and luster.
uu Intermolecular forces—such as dipole-dipole forces
and London dispersion forces—exist between certain types of molecules. Hydrogen bonding is a special case of dipole-dipole forces.
A Tale of Four Electrons
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In Part 4, students describe their four electrons meeting
for coffee and comparing and contrasting their experiences. The covalently bonded electron claims that all
bonding is really covalent in nature. The other electrons
either agree or disagree and defend their reasoning.
Students have four weeks to complete the project—
including two class periods and four “homework-free”
nights. After we discuss the assignment as a class, students
are asked to come prepared to try out their stories with their
classmates the following day.
During their first in-class workday, as students discuss
their plots with a partner and match them with chemical
concepts, they discover that the assignment is more difficult
than they thought. I rotate around the room, discussing any
uncovered misconceptions. Because students use chemistry
concepts to create their own “world,” they review the concepts in a highly interactive and engaged way.
Students then have two weeks to create a draft outline of their stories with incorporated concepts. Once
submitted, I review the outlines to make sure students
follow the story line and demonstrate understanding of
the concepts. They receive a preliminary grade based on
correct concept inclusions, cohesiveness of the story, and
creativity. I also suggest ways to improve stories for those
with low scores.
Students then have two more weeks and three more
homework-free nights to work on their tales. During the
second in-class workday, two weeks after the first, there is less
discussion; students spend most of their time incorporating
missing concepts. I wander around the room—looking over
students’ shoulders, asking about their plots, and trying to
catch any misconceptions.
As the assignment deadline nears, I begin to overhear
students discussing their plots and characters. Although
some groan about the workload, students are clearly proud
of their final creations.
G ra d i n g
As expected with an assignment covering so much material,
grading is a major task. This is where the grading sheet (see
“On the web”) comes in handy. I also have students submit
Extensions.
Figure 2
This assignment could be used for any difficult
or complex science concept. The biology curriculum at my school includes a similar exercise,
in which students write a two-act play about
the steps of photosynthesis. This year, I tried a
similar approach in a lower-level chemistry class
to assess students’ understanding of the law of
conservation of matter in a “copper cycle” lab,
in which copper is reacted with a series of reagents. This forms different copper salts and
eventually transforms the copper back to the
metallic state. Beginning students often do not
understand that the same copper atoms are
carried through the sequential reactions. Asking students to describe themselves as a copper atom moving through the cycle allows me
to see how they view the transformation on a
submicroscopic, particulate level.
For many years, my wife, Sharon Burgmayer, a
professor at Bryn Mawr College, has given students
the option of writing an “elemental profile” in lieu
of an in-class exam. The goal of this profile is to
develop a “personality” for the element, what she
describes as “literary character development” in
the form of a letter to the student’s family describing a new friend. Grading is based on creativity, the
number of connections made between chemical
behavior and “personality,” writing quality, and the
accuracy of the chemistry described.
Chemical bonding vocabulary.
Introduction
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chemical bond
covalent bonding
ionic bonding
metallic bonding
nonpolar covalent bonding
polarity
polar-covalent bonding
Covalent bonding
u bond energy
uu bond length
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chemical formula
diatomic molecule
double bond
electron dot notation
Lewis structure
lone pair electrons
molecular compound
molecular formula
molecule
octet rule
resonance
single bond
structural formula
triple bond
unpaired electrons
Ionic
uu formula unit
uu ionic compound
uu lattice energy
uu polyatomic ion
Metallic
uu band gap
uu conduction band
uu ductility
uu electrical conductivity
uu heat of vaporization
uu luster
uu malleability
uu thermal conductivity
uu valence band
Intermolecular forces
uu dipole
uu hydrogen bonding
uu instantaneous dipole-dipole
attraction
uu intermolecular force
uu London dispersion force
uu molecular polarity
uu permanent dipole-dipole
attraction
February 2011
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Figure 3
Story line.
Overview: To consolidate your understanding of basic
bonding principles, write a story about four electrons
that start their lives in individual atoms, but end up in
ionic, metallic, polar covalent, and nonpolar covalent
compounds. There should be four parts to your story.
Part 1: Life before bonding
1. Name each electron. The name should creatively
reflect the bond type that electron will experience.
2. To start, each electron should reside on an atom
appropriate for its eventual bonding.
3. For each electron, briefly describe its atom using
atomic theory (include Effective Nuclear Charge
[ENC]) and describe the electron itself (which should
be a valence electron) with an electron configuration.
their stories electronically (see “On the web”) to eliminate
paper handling and check for plagiarism.
To simplify the grading process, I ask students to submit
their work using Microsoft Word’s “bookmark” feature to
highlight and bookmark all sentences related to a concept or
vocabulary word. That way I can skim each story, checking
for the requested concepts and vocabulary bookmarks, and
review their understanding. An internet-based system such
as Google Docs (see “On the web”) can also be used, but I
prefer Microsoft Word because the bookmark feature allows
for explicit naming. Stories missing vocabulary, concepts, or
both are returned for revision. For this assignment, students
earn points in four areas:
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Part 2: The bonding experience
1. Pick an appropriate atom to bond with your
electron-containing atom to form an ionic, metallic, polar covalent, or nonpolar covalent bond.
2. For each bond type, describe the bond-forming
process. Describe what your electron experiences
as the bond is formed. You may use illustrations
from the Bonding Images file I have provided, but
the illustrations cannot be the primary way used
to describe the bonding process.
Part 3: Results of bonding
1. Have your electron describe (in his or her own
words) the results of the bonding on both a
molecular and everyday level. Make sure you describe the expected physical properties for each
type of bond. Also describe any intermolecular
forces that the electron might experience.
Part 4: Discussion
1. Imagine your four electrons meet for coffee at
a local diner. Create a conversation comparing
and contrasting their experiences. As part of the
conversation, include a claim by the covalently
bonded electron that “all bonding is really just
different forms of covalent bonding.” Have the
other electrons respond to that claim. Please be
aware that there is no right answer when it comes
to the idea that all bonding is really covalent in
nature. Both metallic bonding and ionic bonding
can be viewed as either an extension of covalent
bonding or different and unique types of bonding.
I am looking for evidence-based reasoning that
is incorporated into your characters’ coffee shop
discussions.
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The Science Teacher
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correct use of vocabulary words (35%),
correct explanation of bonding concepts (30%),
story line (20%), and
creativity (15%).
As I read each story, I tally misused vocabulary words and
review each of the 14 bonding concepts. This is easier than
it might seem, since certain words are commonly misunderstood. Though almost all students include the 14 concepts in
some way, some simply list the concept, which gets them no
credit. The grading sheet clearly states that full credit is only
given if students incorporate the concept into their story in a
way that demonstrates understanding.
I pay special attention to the coffee shop discussion in Part
4, in which students are asked to think critically about bonding. There is no right answer when it comes to the idea that all
bonding is really covalent in nature. Both metallic bonding and
ionic bonding can be viewed as either an extension of covalent
bonding or a different and unique type of bonding. So I look
for evidence-based reasoning and how it is incorporated into
their coffee shop discussions. Figure 4 is an example from one
student’s story.
Reflection
I have used this assignment for two years. Students admit
that this is one of the most difficult assignments in my class.
The sheer number of concepts and vocabulary words that
must be knit together into a cohesive story is daunting. Yet
most students are proud of their achievements, and rightly
so—many demonstrate a sophisticated and nuanced understanding of the types of bonding and their relationships.
Because students are using concepts to create their own
“world,” they learn and review concepts in a way that is
interactive and engaging. It is clear when a student does
not understand a concept or vocabulary word because he
or she uses it perfunctorily, rather than tightly integrating
it into the narrative or character descriptions.
I also have fun reading the stories. Compared to test essays, reading these is pleasurable, and even makes me laugh.
A Tale of Four Electrons
Figure 4
A d d re s s i n g t h e S t a n d a rd s .
Part 4 of one student’s tale.
The following National Science Education Standards
(NRC 1996) are addressed in this project:
Below is part of the coffee shop discussion from one
student’s tale; the full conversation is available online
(see “On the web”). (Note: Crystal is a valence electron
from a sodium atom; Frost is from an oxygen atom; Roger is from nitrogen; and Nemo is from a gold atom.)
Science Content Standard: Physical Science (p. 176)
Structure of atoms
uu Chemical reactions
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Assessment Standard B (p. 79)
Achievement and opportunity to learn science
must be assessed.
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The four electrons met again at the local coffee shop to
compare their bonding experiences…
“You’re absolutely wrong, Frost!” Crystal exclaimed.
“Covalent bonds don’t experience more interactions
than ionic bonds. It’s just that my sodium was attracted
to chlorine, and the chlorine was attracted back. Ionic
bonding isn’t a one-sided affair!”
“I suppose,” Frost replied. “But if you think about it,
our bonds are similar. Sure, your bond didn’t have any
molecules or polarity, but in the end it’s all about filling
up that outer shell with the octet rule.”
“Absolutely,” Roger said. “You know, our bonding is
basically the same. Our atoms both attracted other atoms. When we bonded, we share[d] electrons.”
“We were sort of similar too, Roger,” Crystal added. “After all, it’s all about filling that outer shell any way you can.”
“I feel so out of the loop here!” Nemo whined. “My
bonding was so much different [than] all of yours! Was
anything the same?”
They all thought for a moment. “Well, sure!” Crystal said.
“Both of our bonded structures were in some type of network; everyone relied on everyone else. Ionic bonds work in
big lattices, and metallic bonds work in big structures, too.”
“You’re right!” said Frost…
Though it is a lot of work for both students and the teacher,
the payoff is an emotional engagement with what can otherwise be a dry subject.
To many students, chemistry is a daunting tower of vocabulary, math, and concepts that does not typically draw on their
creative talents. Those who like to write or are mathematically
challenged love the assignment. They see it as a way to demonstrate chemical understanding with words, not numbers.
After completing the assignment, one student wrote, “I am
interested in creative writing a lot, so I was ecstatic when I
found out about the story option for the project.”
G o i n g fo r wa rd
Looking to the future, I wonder about distributing this assignment over the entire bonding unit. Students might write Part
1 (life before bonding) as the class starts the bonding unit, and
Parts 2, 3, and 4 after it is completed—allowing more time to
build concepts into their stories. The benefit of this staged ap-
Assessment Standard D (p. 85)
uu Assessment practices must be fair.
proach might be that as students work through the unit, they
can imagine their four elemental electrons moving through
the processes of bonding—making the unit less abstract. I
also wonder about devoting one period to sharing completed
stories, particularly the coffee shop conversations. Since the
relationship of covalent bonding to other bonding forms is
not clear-cut, discussion about the coffee shop conversation
could open the topic up in a way that a straight “chemistry”
discussion might not.
To many students, the topic of bonding is abstract, filled
with foreign vocabulary and bizarre concepts—far from their
experience of the “real world.” This assignment attempts
to concretize bonding by having students create their own
world—one that they can more closely identify with and use
to demonstrate their chemical understanding. n
Paul Burgmayer ([email protected]) is a chemistry teacher
at Great Valley High School in Malvern, Pennsylvania.
Author’s note
Though I believe there are many advantages to this more rightbrained approach to assessing bonding, personifying atoms as characters in a story does not sit well with some. However, I would argue
that the dual role of assessing students’ understanding and engaging
students in their own learning is worth the trade-off. High school
students are sophisticated enough to understand that this is a creative
writing exercise, not a rigorous scientific explanation of fundamental
forces—a distinction that I emphasize throughout the project.
On the web
A Tale of Four Electrons assignment, grading sheet, and full coffee
shop conversation: www.nsta.org/highschool/connections.aspx
Electronic story submission: http://turnitin.com
Google docs: http://docs.google.com
Reference
National Research Council (NRC). 1996. National science education
standards. Washington, DC: National Academies Press.
February 2011
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