Basic Chemical Thermodynamics - Elements of Environmental Engineering: Thermodynamics and Kinetics - page 15

TABLE 2.1
Major Developments in Thermodynamics over Two Centuries
Year Person Contribution

1760-1766 Joseph Black Calorimetry
1842 Julius Meyer Conversion of heat to work, and vice
versa
1843-1852 James Joule Heat, work, and the first law
1848-1851 William Thompson Absolute temperature scale and the
second law
1854-1865 Rudolph Clausius Concept of entropy
1873-1878 Josiah Willard Gibbs Chemical thermodynamics, chemical
potential, phase rule
1882 H. von Helmholtz Equilibrium, free energy
1884-1887 Jacobus van't Hoff Equilibrium constant, solution theory
1906 Walter Nernst Heat theorem (third law)
1927 Franz Simon Third law
1900-1907 Gilbert N. Lewis Fugacity, nonideality
1929 W.F. Giauque Third law verification
1931 Lars Onsager Nonequilibrium thermodynamics,
reciprocity relations
1949 Ilya Prigogine Irreversible processes, dissipative
structures
Source: Laidler, K.J. 1993. The World of Physical Chemistry . New York, NY: Oxford University
Press.

properties of phenomena” that does not rely on any assumptions on “hypothetical
constituents.” Thus, the laws of thermodynamics have stood the test of time and are
probably inviolable.

2.2.1 Z EROTH L AW OF T HERMODYNAMICS
One of the fundamental system variables in thermodynamics is temperature. The
zeroth law states that if two systems are in thermal equilibrium with a third, then
they are also in thermal equilibrium with each other. This allows us to create a “ther-
mometer.” We can calibrate the change in a property, such as the length of a column
of mercury, by placing the thermometer in thermal equilibrium with a known physi-
cal system at several reference points. Celsius thermometers use the reference points
fixed as the freezing and boiling points of pure water. If we then bring the thermometer
in thermal equilibrium with a human body, for example, we can determine the body
temperature by noting the change in the thermal property. This law also establishes a
temperature scale; that is, only a system at a higher temperature can lose its thermal
energy to one with a lower temperature, and not vice versa. The International Union
of Pure and Applied Chemistry (IUPAC) has adopted the kelvin as its unit of temper-
ature, which is the fraction 1/273.16 of the thermodynamic temperature of the triple
point of water (IUPAC, 1988).