Cathedrals of Science

It is known that in the blast furnace the reduction of iron oxide is produced by carbon monoxide, according to the reaction

Fe3O3 + 3CO = 2Fe + 3CO2,

but the gas leaving the chimney contains a considerable proportion of carbon monoxide, which thus carries away an important quantity of unutilized heat. Because this incomplete reaction was thought to be due to an insufficiently prolonged contact between carbon monoxide and the iron ore, the dimensions of the furnaces have been increased. In England they have been made as high as thirty meters. But the proportion of carbon monoxide escaping has not diminished, thus demonstrating by an experiment costing several hundred thousand francs, that the reduction of iron oxide by carbon monoxide is a limited reaction. Acquaintance with the laws of chemical equilibrium would have permitted the same conclusion to be reached and far more economically.(p. 16)

Comment: The research in science is driven by economics and is itself an economical process.

So while at the end of the 19th century free energies were known to be the key to determining chemical affinity, they were elusive experimentally. But measuring heats of reaction was easy --- just let the reaction take place in a calorimeter (a sealed vessel immersed in a water bath) and measure how much the temperature of the water increased or decreased. If only a way could be found to determine free energies directly from heat measurements! Lewis's new equation suggested it could be done. ... Lewis's method was theoretically correct but was not a practical suggestion. (p. 46)

Comment: Heat is always easier to measure than free energy, or entropy. The whole thermodynamics seems to how to relate heat with other factors such as work.

The third law of thermodynamics can be stated a number of different ways: that the integration constant in Lewis's equation may be set to zero, that the free energy and heats of reaction approach each other asymptotically at very low temperatures (Nerst's prefered formulation), or that the reaction's change in entropy --- a measure of the randomness diue to heat or atomic disorganization --- is zero at absolute zero. Unlike the first two laws of thermodynamics, which were developed in examining how steam engines produce work, the third law's practical impetus was chemical --- the desire to obtain free energies from heat measurements, and Henri le Chatelier, Lewis, RIchards, van't Hoff, and Haber had all attacked the problem. (p. 82)

Comment: Think more about it and see if it can be related to my works.