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Most of use who teach chemistry want students to
understand what we teach them. But many students,
perhaps most, do not try to understand. Even if they set out
trying to understand they usually soon conclude that it is too
difficult, at least in the time they have available, and they
resort, like the others, to learning the material.
By learning they mean memorizingnames of substances,
formulas, definitions of oxidation and reduction, shapes of
orbitals, recipes for assigning oxidation numbers and doing pH
calculations, etc., etc. Most students do not particularly
object to doing this because it is what they did in high
school and is what it means to study. Many will object
to being expected to understand, as they find it
easier to memorize and most of them have little
understanding of what it means to understand.
Surprising as it may seem to us, they see chemistry as very
abstract, very difficult, and unrelated to real life. But this is perhaps not so
surprising if we remember that for these students, chemistry
consists of a large amount of apparently unrelated, irrelevant,
and useless material that they have memorized rather than
understood! Their main objective is to pass the course and
get on to something they consider more interesting and
more useful. They take from the course very little of value
in other courses or in later life and little, if any,
understanding of what chemistry is really aboutmerely a
conviction that they will never understand it. Over many years I
have noticed that when I meet people socially and reveal that
I am a professor of chemistry, they are amazed. How
could an otherwise normal-appearing sort of guy possibly
understand that stuff? They often admit, somewhat
apologetically, that chemistry was their worst subject at high school or
university or that it was the most difficult of all the
subjects they took. Why do I rarely meet anyone who tells me
chemistry was fascinating or exciting, or at least
interesting? Why do most students find chemistry so abstract and
difficult? Why do they not understand the chemistry that
we try to teach them?
Chemistry: The Relation between the Microscopic
and the Macroscopic
Many of us have felt for a long time that there must
be something wrong with what we are teaching, but there
has been very little agreement about what is needed to
change the course so that students will not find chemistry so
difficult, irrelevant, and abstract. One problem is that
students have difficulty making the connection between the
macroscopic world of observations and the microscopic world
of atoms and molecules. Yet it is this aspect of chemistry
that sets it apart from other sciences. If students do not
make this connection, they fail to see the relevance and importance of chemistry to the real world. An understanding
of this connection is probably the most important thing that
a student can get out of an introductory course.
Why Has There Been So Little Change in the
Course and the Textbook?
General Chemistry has been discussed at
countless conferences and symposia, in task forces and
committees, and in department meetings; but little change has
occurred and General Chemistry remains much as it was 20 or
even 40 years ago. Why? One reason may be that textbooks have
not changed. No widespread change can occur until a
new kind of text is published and widely adopted. There
are many well written and lavishly illustrated texts, but almost
all of them treat the same conventional material in more or
less the same conventional way. No matter how excellent these texts appear to the
instructors who choose them, they have not succeeded in
interesting the vast majority of students or in providing them with
an understanding of chemistryor even with useful
information that they remember and use later in life.
Why have so few textbooks tried a new approach?
Publishers are reluctant to invest in unconventional books
on the chance that one might become a best seller and
revolutionize General Chemistry. Even authors who are
convinced of the need for change are reluctant to write a book that
is too unconventional because of the difficulty of finding a
publisher and getting it adopted. Why have none of the few
nonmainstream books that have been published been
widely adopted, leading to widespread reform of General
Chemistry? Because most instructors do not see the need
for change, or do not have time to adapt to a new text and
write new course notes? Because no author has yet hit upon
the right formula for stimulating the much-needed change?
Who Will Initiate and Support Reform?
It seems to me that discussion has gone on
long enough. We will probably never get widespread
agreement on how to reform General Chemistry until a truly new
textbook is published, which influences enough teachers
to change that the new way of teaching becomes the
accepted way. Getting such books published and adopted will
need some initiative from bodies such as the National
Science Foundation, the American Chemical Society, or one or
more of the large chemical manufacturers. Their support and
financial assistance will be required not only to subsidize
the writing and publication of such books, but also for
retraining workshops for instructors. These organizations
could make no more important contribution to the future of
chemistry than to provide this support.
Some Suggestions for Future Textbook Authors
In the hope of stimulating discussion, I make a few
suggestions for consideration by future textbook authors.
1. Forget about the needs of chemistry majors.
Very few students in General Chemistry will become chemistry
majors and only a small number will take even one
more chemistry course. Although it is not the main reason
for reforming the course, we hope to persuade more
students to become chemistry majors. However, there is no need
to include material in the text simply because it will
be needed by majors. When the students' enthusiasm
for chemistry has been ignited they will easily and eagerly
absorb this material in the majors' courses.
2. Continually emphasize the relationship between
the macroscopic world of observations and the
microscopic world of atoms and molecules. This relationship is
the unique aspect of chemistry, and understanding it
makes chemistry alive and relevant. Demonstrations of the
properties of substances and reference to the role of these
substances in the real world, followed by explanation of
the observations in terms of the atoms and molecules of
which substances are composed, is essential. Putting
observations first shows students that the theories and
principles that are so large a part of General Chemistry are
there not just to be learned, but to help in understanding
these observations.
3. Cut out unnecessary details and busy work;
concentrate on what is needed to understand chemistry.
Why start a textbook with details about the names and formulas
of substances? This is boring. Show students some real
chemistry. Bring in what is essential for naming and
writing formulas of substances only when they are being
discussed. How many chemists ever bother to balance an
equation, particularly the complicated redox equations so
common in textbook exercises? A few students will enjoy the
challenge, but are they learning chemistry? Although the
principle is important, time spent balancing any but the
simplest equation is time better employed on other topics.
Is it really important that students know how to calculate
the pH of a solution when they will never have to do such
a calculation again? Even if at a future time they do need
to know the pH of a solution, they will use a pH meter.
This will give them a more accurate (in some cases much
more accurate) value than the simplified calculation
they learned (and have probably forgotten) how to do in
General Chemistry. Do students really need to learn the
shapes of orbitals? These shapes cannot be made
understandable to students at this level. Is it not enough to
understand that atoms are held together by the electrostatic
attraction between electrons and nuclei? Details of bonding
theories should be left for chemistry major courses.
4. Show the broad scope of
chemistry. Students in General Chemistry have a broad range of interests. Why
not show them that chemistry is indeed the central
science, basic to understanding all materials, whether organic
or inorganic, synthetic or naturally occurring; show them
how chemistry is relevant to the geologist, biologist,
engineer, astronomer, doctor, environmentalistindeed, to
everybody? Make General Chemistry truly general, rather
than the elementary physical chemistry course it is at present.
5. Make the textbook
shorter, so that the material can be covered at a pace that allows time for
understanding. Many students are overwhelmed by the amount of
material and detail in most texts.
Perhaps these suggestions will inspire some author
to write, some publisher to publish, and some organization
to support the revolutionary text that we need. Perhaps
such a text will follow only some (or none) of my suggestions,
but I hope the questions I have raised will provoke some
potential authors to propose their own solutions. The
approach of the year 2000 is inspiring many to think about
change. Let us hope that chemists will be able to celebrate the
new millennium with a new, more inspiring, approach to
General Chemistry.
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