I frequently meet parents – successful physicians, lawyers, and other professionals – who recall their high school and college chemistry experiences with something less than pleasure. Things that cause discomfiture include the apparent memory-intensiveness of chemistry, the weird problems, and the obsessive attention to very tiny measurements or to unimaginably large numbers (for example, the number of atoms in twelve grams [a modest size stick of charcoal] of carbon is 602,210,000,000,000,000,000,000, a number greater than all the pennies spent by all the economies in the history of the world!). On the surface of it, chemistry seems remote and inaccessible. However, in my nineteen years of teaching chemistry – predominantly to sophomores – I have yet to encounter a student who did not go away from my course without the sense of mastering the fundamentals of chemistry. For some – those bound toward the science/math/tech track – it was pretty easy. Their brains somehow find that chemistry’s inherent logic and internal consistency made sense. For others, the mysteries of chemistry come with some effort; however, with perseverance and, perhaps a little help from their friends (and their teacher), they do well. For a few, chemistry proves quite daunting. These students require more attention, more practice, more stick-to-itiveness, even as they tend to shy away from extended practice. The success rate for these students in Introductory Chemistry is still very good, but it comes with considerably more effort on both the student’s and the teacher’s part. I personally know two people who were on the doctor pathway in college, but changed majors after failing organic chemistry (organic chemistry is the most memorization-based branch of chemistry; for example, the chemical name for Prozac® is “N-methyl-3-phenyl-3-α-α-α-trifluoro-p-tylol-oxypropylamine hydrochloride”, and there is no other way to master its nomenclature besides learning the rules by rote memory).
So, just how hard is chemistry, anyway? There’s no escaping the complexity of problem-solving in chemistry. Yet, in Introductory Chemistry, students internalize a problem-solving method that is extremely powerful; one that will serve them well in all future science classes both in high school and in college. Mastering a consistent problem-solving method (analysis, planning, computation, and evaluation) takes time. No one comes to chemistry with this methodology fully in place. Indeed, the key difference between 8th grade physical science/chemistry and high school chemistry is the latter’s focus on quantitative problem solving, which is what real chemists do, after all. The basic concepts are the same (although I have found sophomore amnesia for 8th grade chemistry to be a common disorder). Students grow into effective problem-solvers, some faster than others. It is important to note that I systematically reduce the memorization load in Introductory Chemistry by allowing students to use the periodic table and the chemical ion table during tests; I generally provide at least a partial formula set for students to use on tests, as well. My focus is on understanding, application, and synthesis rather than raw memorization.
Let me briefly address the cognitive functioning of the average sophomore. A friend and former colleague of mine discovered during her PhD dissertation work in science education that seventy percent of freshman chemistry students operate predominantly at the Piagetian level of concrete operations. Piaget’s ages and stages work with cognitive development suggested that most young people move from concrete operations – a level that allows them to solve complex problems, but only when they have physical means (i.e. manipulative objects, learning tools) at their disposal – to formal operations at about the age of twelve. Formal operational thinking allows us to understand figurative language and to truly grasp things like algebra, metaphors, and archetypes. My friend found that most 19 year-olds were still processing information concretely, yet they were, for the most part, passing freshman chemistry, many with A’s and B’s.
Chemistry, then, would seem to be a surprisingly concrete science. It yields its secrets to those who keep at it; who, in a word, persevere. I do not expect my students to know how to solve complex chemistry problems when they come to me. I do, however, ask them to plug away at the process until they achieve mastery, and this involves, essentially, a year-long program of study. Parents should be patient. Even if a child is struggling (and he or she should be consistently encouraged to assiduously apply themselves) with chemistry in September, I can say with confidence that he or she will be OK with the discipline by November, December… (although I can not guarantee that everyone will opt for a chemical engineering major at Georgia Tech – someone has to teach history and fill the law schools).
-- Mark McCandless
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