The back page shows the individuals and agencies whose financial support has been vital. Academic support from my mentors, Dr. Michael Clyne and Dr. Donald Setser, laid the groundwork. Research support from students and staff has been essential: They do the work, and I get to talk about it. Above all, my wife, Hazel, supports me.

Pollutants found in car exhaust are formed in a number of different ways, depending on the pollutant. Consider a flame from a candle, a not-too-hot blowtorch, or a Bunsen burner. A fly screen or wire gauze lowered into the flame extinguishes it above the gauze even though fuel and air are present. Taking the heat away puts the flame out. In the same way, the cold walls of the cylinder in a car engine extinguish the flame in a layer (the quench layer) within a millimeter or so of the walls. The rising piston scrapes this layer of unburned air/fuel mixture off the walls. For this reason, a car without a catalytic convertor is bound to emit some unburned fuel in its exhaust.

Carbon monoxide formation depends on chemistry. Fuel can be regarded as containing about two hydrogens for every carbon (CH2). This crude approximation obscures all the fascinating chemistry of real fuels just as the formula CH2O for a tree or a human being obscures a good deal of biology and individuality. However, CH2O is adequate to operate a wood stove or a crematorium, thus we will use CH2 for "fuel." Air is approximately one oxygen and four nitrogens, thus O2 + 4N2. The majority of exhaust is therefore nitrogen, and the chemistry of a properly operating (stoichiometric) car is as follows: