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"There is so much to learn. I can't possibly remember it all."
"I study for hours but still don't do well on tests."
"I've never been good at science."
"I'm not good at math."
"I understand the problems when the teacher does them in class but I can't do them by myself at home."
"Why do I have to know this?"

Diane Bunce will tell you that chemistry should not be that difficult a subject to learn, which she did recently to a roomful of chemistry students at the ACS National Meeting in Orlando. Bunce, Associate Professor of Chemistry at the Catholic University of America (Washington, DC), specializes in chemical education and she believes that there is a mismatch between the way chemistry is taught and the way students learn that hampers their success.

The first step on the road to learning chemistry successfully is don't see chemistry as isolated facts. "If you are studying chemistry as a series of isolated facts, then there will be too much information," says Bunce. A good example is organic chemistry, which consists of a few basic principles but everything you learn is based on these principles. You may feel overwhelmed by the amount of material you have to learn but you can't learn it all the night before an exam, as you attempt to memorize as many pieces of information as you possibly can. Then after the exam, your brain dumps the information because of the overload.

She suggests that the key to avoiding this strategy is by learning to see the integrated whole. Research indicates that people remember no more than 7 (±2) new facts or "chunks" of information. So we expect all people to remember at least 5 new pieces of information; everything else is "dumped". A chunk is a piece of information that can be small or large and the size of the chunk depends on previous knowledge. The more experience we have with a subject, the larger the chunk.

Bunce recommends learning to increase the size of your chunk by writing it down and relating chunks of information. Study by yourself and learn individual chunks or concepts, then take it to the next level by connecting the chunks or concepts to each other.

Try this exercise. Compare and contrast the following:

+How are ionic and covalent bonds related?
+What is the difference between an atom and a molecule?

In the first question, if an ionic bond is formed when electrons are transferred from one atom to the other and a covalent bond is formed when electrons are shared between atoms, are these two bonds distinctly different or are they two extremes of a continuum? Every covalent bond has ionic characteristics and vice versa. In the second example, a molecule is a collection of atoms linked by covalent bonds. Atoms are stand-alone particles made up of protons, neutrons and electrons. There are no covalent bonds within atoms.

The bottom line is that this is how a chemist looks at the situation. Chemists see chemistry as an integrated web of concepts. This is why there can seem to be a mismatch between homework assignments and exams. "Homework assignments often focus on individual concepts while exam questions can ask you to integrate two or more concepts," says Bunce. "The professor probably believes that if you understand the individual concepts, then you will be able to answer a question that relies on an integration of two or more of them. You, the student, are probably expecting the professor to ask single concept questions, creating a mismatch in expectations that can lead to student frustration."

Concept Maps

One method Bunce recommends to help understand the relationship between concepts is to draw a concept map. A concept map is a schematic diagram that shows the relationship among concepts. Concepts are usually enclosed in circles or boxes, and a connecting line between two concepts indicates relationships between concepts. Words on the line specify the relationship between the two concepts. The concepts in a concept map are presented hierarchically, from the most inclusive at the top to the least inclusive at the bottom.

Concept maps help you see the connections between concepts you already understand; connect new ideas to knowledge you already have; and structure the information in such a way that you can add new ideas in the future. Developing a concept map fosters a better understanding of the material presented in class and highlights areas where you may still be uncertain.

Example: A concept map illustrating the proposition, "Without the industrial chemical reduction of atmospheric nitrogen, starvation would be rampant in third world countries."

"I study for hours…."

According to Bunce, "Memorizing, rather than understanding, is the least robust way of learning." She advocates the constructivist view of learning where the learner must actively engage in the learning process and new knowledge is constructed by integrating incoming information with information that is already present in the memory.

How does integration take place? Access information that you already have in memory. When you experience new information through lab, a demonstration, or homework, take time to integrate the new knowledge with your prior knowledge. Then, explain the concept to someone else. Work with other students to explain a concept. Next try "directed paraphrase" where you explain the concept to someone who is not in the class. (For example, explaining equilibrium to your mother.)

"I'm Not Good At Math (Science)"

"If you can add, subtract, multiply, and divide," says Bunce, "then you can do most of the math in a chemistry class. The problem is that you don't know which numbers to add, subtract, multiply, or divide." The problem is not math, according to Bunce, but logic and analysis.

If you understand the problem when the teacher does it but can't do it on your own, your first task is to recognize what kind of problem it is. Can you identify the information given in the problem? Can you identify what is asked for? For example, if you recognize that the problem involves stoichiometry, is it a mass-mass problem, mass-mole, mole-mole, or mass-volume?

Once you've categorized the problem, Bunce recommends writing down the rules, equations, or definitions that you might need to solve it. Draw a diagram of the steps you will use to solve the problem. Start with what is given and end with what is asked for, then do the math. Review the steps you used to solve the problem because this will be helpful when you solve another problem like it.

If your teacher uses this technique in class, but you still have trouble, then review your notes. Did you write down everything the teacher said or, do you have one string of numbers with everything crossed out? Bunce advises against solving problems with your hands on the calculator. Take the time to analyze the problem first. Do you remember how you solved a problem? Do you compare one solution to another?

Solving problems in chemistry requires analyzing the problem before you use your calculator:

• Identify what's given and asked for;
• Categorize the problem according to type;
• Write down relationships, equations, or rules needed to solve the problem;
• Draw a schematic diagram of the steps to the solution;
• Do the math; and
• Review the problem.

How many grams of sulfur dioxide?

"Why Do I Have To Know This?"

"All chemistry topics should be related to something in the real world," says Bunce, "and if you don't see the relationship-ask."

Learning chemistry requires understanding the material, not just memorizing it. This includes seeing the material in your mind, and being able to explain it to someone else. Learning chemistry requires being awake, being involved, relating one concept to another, acquiring ownership of this knowledge, and having a nonstressful (read: not a test!) opportunity to explain that knowledge to others.

Additionally, you can improve your test-taking strategies. For example, on multiple-choice questions, read the question with the answers covered up. Analyze what the question is asking before you decide on an answer. Then generate your own answer before looking at the answers provided. If your answers don't match the answer you came up with, then go back to the question and reanalyze.

On essay questions, read the entire question. Pick out the pertinent information. Ask yourself what topic or topics is this about? What do you know about these topics? Jot down some key concepts that could be used to solve the problem. Use the information you have to outline a logical answer. As you write your answer, read it over to see if it answers the question asked, is logical, and is specific. If you go blank on a test, skip the question and come back to it later. When you come back to the question, if you are still drawing a blank, jot down something you know that might be used to answer the question. If nothing else, go for partial credit.

Everything Diane Bunce had to say boils down to focusing on what you can control and contribute to your success in the classroom. You won't get to choose your textbook or who is teaching the class, but you can identify ways to help you process, organize, highlight and identify the information in a way that is useful to you.

Corinne Marasco is Content Manager of JobSpectrum.org.

Related Resources

For those students studying for ACS exams in General or Organic Chemistry, Diane Bunce recommends the two new student guides available for purchase from the ACS Exams Institute. They cost $10 (General) and $15 (Organic). The guides use questions from old ACS exams, analyze the correct answer and explain why the other choices are wrong. Additional problems and practice tests are provided along with an answer key.

Kean, E. and Middlecamp, C. How to Survive (and even excel) in General Chemistry. McGraw-Hill, Inc.: NY 1994.

Dr. Fred Senese of Frostburg State University offers 10 tips to pass your next chemistry exam.