In the history of chemistry, an affinity table was an arrangement of chemical species ordered such that the species at the head of each column had a chemical attraction for each species below with each potential reactant listed in order of decreasing force of affinity to the header species. The original affinity table was the 1718 Tableau des différentes Rapports Observées entre Différentes Substances (Table of the Different Relations Observed between Different Substances) made by French physician and chemist Étienne Geoffroy, as shown below. After 1882, wherein German physician and physicist Hermann von Helmholtz showed that the measure of affinity is "free energy", affinity tables were soon replaced by free energy tables. [1]
In Geoffroy’s table, to elaborate, at the head of each column is a header species with which all species below can combine or have a rapport with. The latter are so placed such that any higher species replaces all others lower in the column from their compounds with that at the head of the table. In other words, the species at the head of the table can potentially react with any species below it. All the species below the header species are ranked by chemical affinity preferences relative to the top species, with a higher rank corresponding to a higher affinity tendency. The species at the bottom of each column, for instance, have the least amount of affinity for the header species. If the bottom species is in a weakly bonded relationship with the header species, any species above it can potentially displace it from its attached partner. [2]

This table led to the development of the science of affinity chemistry and to the various laws of affinity; numbering up to ten, depending on which chemist was sourced. The best known is Plato’s ‘like attracts to like’ affinity law, e.g. water-to-water or fire-to-fire, etc. The peak of the science of affinity chemistry culminated in the publication of the popular 1775 textbook A Dissertation on Elective Attractions by Swedish chemist Torbern Bergman. The center piece of Bergman’s book, was a fifty-column, fifty-row, chemical affinity table, the largest ever assembled, showing thousands of possible chemical reactions in schematic form between various chemical species, such as, for example, the famous ‘double elective affinity’ (double displacement reaction), where two chemical units, AB and CD, exchange or displace partners to form two new evolved species AC and BD. [2]

AB + CD → AC + BD

Origin
The affinity table was the spark of the chemical revolution. The beginnings of the chemical revolution centered around the revival of Leucippus’ atomic theory through the works Descartes (1637), French mathematician Pierre Gassendi (1649), English chemist Robert Boyle (1661), and English physicist Isaac Newton (1686). In this revival, the concept of the ‘molecule’, from French word molécule, originating from the Modern Latin molecula, a diminutive of Latin word moles or ‘mass’, was born, generally defined as a small unit of mass or structure comprised of two or more atoms. [3]

Unique among this group was Newton, who conceived of molecules as being structures of atoms attached together by a chemical force of affinity. He outlined his atomic chemical force affinity bonding theory in the ‘Queries’ section to his Opticks. To cite one example of Newton’s description of a gradient of affinity reactions, he states ‘and is it not for want of an attractive virtue between the parts of water and oil, of quick-silver (Hg) and antimony (Sb), of lead (Pb) and iron (Fe), that these substances do not mix; and by a weak attraction, that quick-silver and copper (Cu) mix difficultly; and from a strong one, that quicksilver and tin (Sn), antimony and iron, water and salts, mix readily?’. [4]

In 1718, during a translation into French of Newton’s Opticks, French physician and chemist Étienne Geoffroy used Newton’s descriptions of affinity reactions to construct the world’s first affinity table, as shown below, containing twenty-four reacting species, detailing specifically what affinity reactions would occur between various combinations of reactants. This table seeded the chemical revolution: [5]

The origin of the concept of the ‘chemical reaction’ stems from this table through the work of Scottish physician and chemist William Cullen. [2] In 1756, in lecture, Cullen utilized Geoffroy’s affinity table wherein he pioneered the use of chemical reaction diagrams by using reaction arrows ‘→’ and bonding brackets ‘{‘ to show the mechanistic steps in each elective affinity reaction. [6]

See also
● Affinity of reaction

References
1. (a) Cahan, David (1993). Hermann von Helmholtz and the Foundations of Nineteenth-Century Science (Ch. 10: "Between Physics and Chemistry - Helmholtz's Route to a Theory of Chemical Thermodynamics" by Helge Kragh). University of California Press.
(b) Quote: "Given the unlimited validity of Clausius' law, it would then be the value of the free energy, not that of the total energy resulting from heat production, which determineds in which sense the chemical affinity can be active." (Source: Helmholtz, H. v. "Die Thermodynamic chemischer Vorgange," SB, pg. 23, pg. 22-29, in Wissenschaftlich Abhandlundgen von Hermann von Helmholtz. 3 vols. Leipzig: J.A. Barth, 1882-95.)
(c) Leicester, Henry M. (1956). The Historical Background of Chemistry, (pg. 206). New York: Dover (reprint).
2. (a) Thims, Libb. (2007). Human Chemistry (Volume Two), (preview), (ch. 10: “Goethe’s Affinities” and ch. 11: “Affinity and Free Energy”, pgs. 371-468) Morrisville, NC: LuLu.
(b) Thims, Libb. (2008). The Human Molecule, (preview), (pgs. 3-5). Morrisville, NC: LuLu.
3. Molecule (from Fr. moléclue (1678), from Mod.L. molecula, dim. of L. moles "mass, barrier"); Online Etymology Dictionary.
4. Newton, Isaac. (1704). Opticks (Query 31: On the small particles of bodies); London: Printers to Royal Society. Note: several editions published between 1704 and 1730.
5. Kim, Mi Gyung. (2003). Affinity, That Elusive Dream – A Genealogy of the Chemical Revolution. Cambridge, Mass: The MIT Press.
6. Crosland, M.P. (1959). “The use of diagrams as chemical equations in the lecture notes of William Cullen and Joseph Black.” Annals of Science, Vol. 15, No. 2, June.