After Mario Molina warned the world that CFCs could damage ozone, and after Susan Solomon showed that his prediction was coming true before our very eyes, the next question was obvious: What do we do about it? Regulating CFCs was the obvious answer, and a complete phase-out was eventually deemed the best course of action. But before this can happen, alternatives to CFCs are needed. This is where the work of scientists like Joseph Francisco becomes important. He is heavily involved with studying the reactions involved with ozone destruction, and the behavior of new refrigerants in upper atmosphere conditions, both with the goal of making sure that the CFC replacements don't cause any ozone damage or other environmental problems.

The work of Joseph Francisco may seem difficult to describe in terms that high school students can understand, but by focusing on the practical ends of his research the students can gain an understanding of why his work is important. The most readily grasped aspect of his work is the testing of potential CFC replacements, to ensure that they are environmentally friendly.

Relevant National Science Education Standards

Unifying Concepts and Processes — Francisco's work explores the intricacies of the chemical systems operating in the earth's atmosphere. In addition, the readings shows what kind of evidence must be obtained before one can conclude that a refrigerant is environmentally-safe, this case the evidence comes in the form of the observations of decomposition products that don't decompose ozone, and in the spectral evidence which indicates whether a new refrigerant is likely to be a greenhouse gas. At a more basic level, the readings shows how spectroscopic data are used to determine the nature of substances, be they reactants, intermediates, or products, in a chemical reaction.

Physical Science — The reading deals with the molecular nature of matter, chemical reactions, and the interaction of matter with energy in the form of UV radiation.

Earth and Space Science — The reading deals with some of the chemical processes occurring in the earth's atmosphere, and the involvement of different forms of energy on those processes.

Science and Technology — The reading probes the technology of ozone-safe refrigerants.

Science in Personal and Social Perspectives - The reading involves an environmental quality issue which is also a human-induced health hazard, plus the use of science in overcoming this global challenge.

History and Nature of Science — The reading explores science as a human activity. In addition, discussion of ongoing research reinforces understanding of the nature of science.

Next: What is a Refrigerant?

The Francisco Group — find out about Dr. Francisco's work firsthand on the official website of his research group, from Purdue University. The site features mpg videos of Dr. Francisco and his group.

References

Kessler, James H., Kidd, J.S., Kidd, Renιe, and Morin, Katherine. Distinguished African American Scientists of the 20th Century. Phoenix: The Oryx Press, 1996.

Good, D. A., Francisco, J. S., and DeMore, W. "Structure and Vibrational Spectra of CFC Substitutes: An Experimental and Ab Initio Study of Fluorinated Ethers CHF₂OCF₃ (E125), CHF₂OCHF₂ (E134), and CH₃OCF₃ (E143)," Journal of Physical Chemistry 1998, 102, 1854-64.