Download Alternative Conceptions in Chemistry Article Review

Tyler Anderson & Chris Bamer
1/22/10
TST Presentation
Secondary Science Methods
Alternative Conceptions in Chemistry
(From The Science Teacher, September 2009)
Article Summary:
Chemistry plays an important role in our society and can be found all around us.
Food science, environmental issues, household chemicals and technology all have
connections to chemistry. It is therefore important and practical to possess content
knowledge in chemistry.
The problem is, chemistry is difficult to learn because many concepts are abstract
and students cannot always easily relate it to their own lives.
Some researchers examining learning in chemistry have suggested that students
understand science concepts on three levels: macroscopic, microscopic, and
symbolic.
Macroscopic understanding refers to things that can be observed in the natural
world. Examples: Acids taste tart, turn blue litmus paper red, and dissolve various
other substances. At 0˚C, water freezes into a solid (ice) and will float on top of
liquid water. Sodium (solid) and chlorine (gas) combine to form sodium chloride
(table salt).
http://www.youtube.com/watch?v=yjge1WdCFPs&NR=1
Microscopic (or submicroscopic) understanding refers to things at a particulate
level, such as molecules, atoms, ions, subatomic particles, etc. Examples: An acid
might be understood as a proton donor. Solid water (ice) floats in liquid water
because it is less dense. It is less dense because of hydrogen bonding and the way in
which water molecules separate and organize into a crystal lattice when freezing.
Sodium donates its one valence electron to chlorine and then these two ions form
the ionic compound sodium chloride (table salt).
http://www.youtube.com/watch?v=QqjcCvzWwww
Symbolic understanding refers to abstract representations of macroscopic and/or
microscopic observations. Examples: An acid can be symbolically represented as
“H+.” Water freezing can be represented as “H2O(l)  H2O(s).” Sodium and chlorine
combining can be represented as “Na(s) + Cl(g)  NaCl(s)”
The true understanding of a chemistry (or other science) concept requires
individuals to understand what is going on at all three levels.
Do Activity 1 – Levels of Understanding
Student Misconceptions:
Often times, submicroscopic and symbolic representations can be misconceived due
to their abstract nature.
3 common reasons for student misconceptions:
1. Take submicroscopic and symbolic representations literally (or
macroscopically). Examples: Atoms are hard spheres, electrons revolve
around the nucleus like planets around the sun, molecules get bigger when
they are heated, atoms are glued together when chemically bonded, etc.
2. Apply macroscopic understandings to their submicroscopic understandings.
Examples: Water molecules are wet, molecules of solids are hard, metal
atoms are shiny, etc.
3. Vocabulary misinterpretations. Sometimes a word may have a meaning
outside of chemistry class that is different than it’s meaning within the
subject. Examples: Students describe atoms like cells because they both have
a nucleus, think of electron shells like egg shells, believe that electron clouds
are like rain clouds, etc.
Do Activity 2 – Common Origins of Student Misconceptions
Connections:
“On one hand, their prior knowledge, along with their models and theories, shapes
how they interpret the natural world and new scientific information; on the other
hand, prior knowledge, in the form of misconceptions, can mask the way
information is interpreted and lead to unacceptable explanations.” (Rochelle, 1997,
from Teaching High School Science through Inquiry).
“Children develop ideas about natural phenona before they are taught science in
school. In some instances these ideas are in keeping with the science which is
taught. In many cases, however, there are significant differences between children’s
notion and school science.” (Driver 1)
Our course readings have thus far focused on a constructivist model of teaching. In
this model, student misconceptions are the starting point for planning and
implementing effective instruction.
It stands to reason that understanding the origin of misconceptions better equips
teachers to facilitate the conceptual progression of their students.
Conclusion:
Being aware of the three levels of understanding can provide teachers with a
context of how student misconceptions can arise. Understanding these
misconceptions and their origins can help teachers tailor their planning and
instruction to more effectively promote student learning.
Work Cited:
Colburn, A. (2009). Alternative Conceptions in Chemistry. The Science Teacher,
76(6), 10.
Activity 1 – Levels of Understanding
Directions: Work with your group to brainstorm a concept that can be broken down
into the three levels of conception. Record your example in the table below.



Macroscopic: refers to things that can be observed in the natural world.
Microscopic (or submicroscopic): refers to things at a particulate level, such as
molecules, atoms, ions, subatomic particles, etc.
Symbolic: refers to abstract representations of macroscopic and/or microscopic
observations.
Level of Conception
Macroscopic
Our Example
Sodium (solid) and
chlorine (gas) combine
to form sodium chloride
(table salt).
Microscopic
Sodium donates its one
valence electron to
chlorine and then these
two ions form the ionic
compound sodium
chloride (table salt).
Na(s) + Cl(g)  NaCl(s)
Symbolic
Your Example
Activity 2 – Common Origins of Student Misconceptions
Directions: Work with your group to brainstorm at least two different student
misconceptions. Categorize and record each within the table. You are free to use the
‘Other’ category but need to be able to explain the origin of the misconception.
Origin of Misconception
Submicroscopic or
symbolic representations
interpreted literally.
Our Example
Atoms are hard spheres
Macroscopic
understandings applied to
the submicroscopic level
Water molecules are wet
Vocabulary
misinterpretations
Electron clouds behave like
rain clouds
Other
Activity 3 – Discussion
What implications, if any, does this have for your teaching?
Your Example
3 Levels of Understanding:
Macroscopic understanding refers to things that can be
observed in the natural world. Examples: Acids taste
tart, turn blue litmus paper red, and dissolve various
other substances. At 0˚C, water freezes into a solid (ice)
and will float on top of liquid water. Sodium (solid) and
chlorine (gas) combine to form sodium chloride (table
salt).
Microscopic (or submicroscopic) understanding
refers to things at a particulate level, such as molecules,
atoms, ions, subatomic particles, etc. Examples: An acid
might be understood as a proton donor. Solid water
(ice) floats in liquid water because it is less dense. It is
less dense because of hydrogen bonding and the way in
which water molecules separate and organize into a
crystal lattice when freezing. Sodium donates its one
valence electron to chlorine and then these two ions
form the ionic compound sodium chloride (table salt).
Symbolic understanding refers to abstract
representations of macroscopic and/or microscopic
observations. Examples: An acid can be symbolically
represented as “H+.” Water freezing can be represented
as “H2O(l)  H2O(s).” Sodium and chlorine combining can
be represented as “Na(s) + Cl(g)  NaCl(s)”
3 common reasons for student misconceptions:
1. Take submicroscopic and symbolic representations
literally (or macroscopically). Examples: Atoms are
hard spheres, electrons revolve around the nucleus
like planets around the sun, molecules get bigger
when they are heated, atoms are glued together
when chemically bonded, etc.
2. Apply macroscopic understandings to their
submicroscopic understandings. Examples: Water
molecules are wet, molecules of solids are hard,
metal atoms are shiny, etc.
3. Vocabulary misinterpretations. Sometimes a word
may have a meaning outside of chemistry class that
is different than it’s meaning within the subject.
Examples: Students describe atoms like cells
because they both have a nucleus, think of electron
shells like egg shells, believe that electron clouds
are like rain clouds, etc.