D A V I D . H E N D E R S O N

The following feature story appeared in the campus publication MOSAIC in September, 1997.

David E. Henderson

Inspiring students to become poets of the laboratory

Students in Professor David E. Henderson's chemistry classes can expect to become poets of the laboratory. In the view of this professor of chemistry, there is little difference between the musings of a poet that result in a memorable work and the imaginings of a scientist that produce a discovery. Scientists, like poets, have to be very creative, he contends.

"The building blocks of a poem are words, and the building blocks of a chemical idea are images of molecules or equations. Even the process of trial and error is the same," Henderson points out.

Henderson, who grew up in the South and who holds a doctoral degree from the University of Massachusetts, joined the Trinity chemistry faculty 20 years ago. Since that time, he has earned a reputation as a demanding, innovative, and accessible teacher. An analytical chemist, he teaches courses in introductory, analytical, and environmental chemistry.

Since he began teaching at Trinity, Henderson says that he has had to modify his pedagogical approach. "The way we process information is evolving due to the computer, multimedia, and TV," he explains. Today, Henderson asserts, the traditional lecture is no longer an effective means of transmitting information. "In my classroom, the lecture isn't so much a lecture as a conversation."

Doing "real science"

To help his students become scientists, Henderson includes a "real science" component in each of his courses. "By doing 'real science,' I mean that the students and I work together on questions for which neither they nor I have the answers. I work as a mentor and an instructor, and they become scientists as we search together for an answer."

A good example of such a scientific investigation is the acid rain project, which is conducted as part of "Introductory Chemistry." In 1991, using a $60,000 grant from the New England Consortium for Undergraduate Science Education, Henderson constructed a computerized weather station on the roof of Clement chemistry building and purchased state-of-the-art high performance liquid chromatography (HPLC) equipment for the laboratory. For the laboratory requirement of the course, students take samples of precipitation, measure the pH factor, titrate the acidity, and then use the HPLC equipment to learn the nitrate and sulfate content. Henderson explains that the source of sulfate pollution is principally power stations, electrical power generation, and coal burning processes. The nitrate in rain is due to emissions from cars, trucks, and power plants.

"By measuring the nitric acid contribution to acid rain and the sulfuric acid contributions to rain, the students can identify what aspect of our economy is generating the pollution," Henderson says. Using those findings, students write technical reports on their research and then have the opportunity to write op-ed pieces for local newspapers.

Chili pepper research

Just as his students are making new discoveries, Henderson is blazing new ground with his own research. On sabbatical this year, he is continuing his research in a field that holds not only his scientific attention but his gastronomic and horticultural interest as well -- chili peppers. Specifically, he and his wife, Susan, a professor at Quinnipiac College, are examining how capsaicin, the substance that makes chilies hot, acts as an antioxidant when heated with oil. Because antioxidants retard the breakdown of fats, both in cooking and in the body, they may also slow the progress of cancer, heart disease, and aging. (Yankee Magazine profiled their work in its August issue and included the Hendersons' favorite recipes, such as "Pasta from Hell.") In his other scholarly pursuits, Henderson has written an introductory chemistry textbook for McGraw-Hill, which was published last year.

By bringing his students into his research, Henderson helps them become scientists and grow confident in what they have learned. Chemistry major Jennifer M. Milham-Becker '99 has served as a teaching assistant in Henderson's "Analytical Chemistry" lab. "I worked with Professor Henderson on his chili pepper research. It's basically organic chemistry, which is something I hadn't studied. Yet he helped me learn and understand what I was doing." William M. Mahoney, Jr. '99, a biochemistry major, has taken two courses with Henderson. "He is definitely a tough teacher. He expects an enormous amount of effort. The work ethic you can develop in this course can be applied to your other work." Biochemistry major Adam M. Slickman '99 agrees. "Academically, Professor Henderson likes to push his students. He wants them to demonstrate that they've learned and are not just regurgitating information."

Helping students to become confident in what they have learned is one of Henderson's strengths, says his colleague, Vernon K. Krieble Professor of Chemistry Henry A. DePhillips, Jr. "What David does is teach students how to accumulate data and then develop confidence in that data -- which is very important for an analytical chemist. He's demanding, sets high standards, and expects students to achieve a certain level of excellence."

Says Henderson of the teaching philosophy that he shares with the chemistry department, "Our goal is to give students a taste of real science as it's actually done. We give students the opportunity to figure out the questions they need to ask, and to ask those questions. My goal is to make my students as successful as possible."

-- Suzanne Zack

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