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2021 ◽  
Author(s):  
Rina Wasserman

Although sodium, potassium, calcium, and magnesium were isolated as the chemical elements by Sir Humphry Davy for the first time at the beginning of the 19th century, alkali salts and hydroxides have been widely known and used since the very ancient time. The word “alcali” & “alkali” was borrowed in the 14th century by literary Roman-Germanic languages from Arabic al-qalī, al-qâly ou al-qalawi (), which means “calcinated ashes” of saltwort plants. These ashes are characterized nowadays as mildly basic. They have been widely used in therapy, cosmetics, and pharmacy in Mediaeval Europe and the Middle East. However, the consumption of these alkali containing ashes, as well as natron salts and calcined lime-based materials used for different customer purposes, like therapy, pharmacy, cosmetics, glass making, textile treating, dyes, brick making, binding materials, etc., was commonly known since the very ancient times. The current review of the archeological, historical, and technological data provides the readers with the scope of the different everyday life applications of alkali and alkali-earth salts and hydroxides from ancient times till nowadays. The review obviously reveals that many modern chemical manufacturing processes using alkali and alkali-earth salts and hydroxides have a very ancient history. In contrast, there has been a similarity of targets for implementing alkali and alkali-earth salts and hydroxides in everyday life, from the ancient past till the modern period. These processes are ceramic and glass making, binding materials in construction, textile treatment, metallurgy, etc. So, this review approves the common statement: “The Past is a clue for the Future.”


Substantia ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 97-120
Author(s):  
Ernst Kenndler

This review is the first in a series that deals exclusively with electrophoresis of ions. Since in modern terminology "electrophoresis is the movement of dispersed particles relative to a fluid under the influence of a spatially uniform electric field”, electrophoresis is not limited to colloidal particles, it includes ions as well. The history of electrophoresis of ions therefore begins in 1800 at the same time as that of electrolysis, because the two phenomena are so inextricably linked “that one cannot happen without the other” (Faraday, 1834). Between 1800 and 1805 about half a dozen different theories of electrolytic decomposition and the movement of the particles - for which we coin the term electrophoretic current - were formulated, all contributing to the discourse, but lacking consistency and none fully convincing. They are discussed nonetheless because most of them fell into oblivion, even though they are interesting for historical reasons. However, from 1805/1806 the predominant theory, formulated by Theodor von Grotthuß and independently by Humphry Davy assumed that polarized molecules of water or dissolved ions form chains between the two electrodes. Only the terminal atoms of these chains were in direct contact with the electrodes and were liberated by galvanic action, but are immediately replaced by neighboring atoms of the same type. This decomposition and recombination of the molecules driven by electric forces which follow the “action at a distance” principle like in Coulomb´s law takes place over the entire chains; they represent the electrophoretic current. However, in 1833 Michael Faraday refuted all previous theories. Two of his groundbreaking findings were of particular importance for the electrophoresis of ions: one was that electricity consists of elementary units of charge. The ions thus carry one or a multiple of these units. The other was the revolutionary theory of the electric lines of force in early 1840s, and of what was later called the electric field. With these findings Faraday fundamentally changed the previously prevailing view of the electrophoresis of ions.


Author(s):  
Richard J. Kahn

In 1795 Barker read Lavoisier’s chemistry, experimented on tainted meat made edible by soaking in alkalis, and began using alkaline therapy such a limewater. He wrote about this to Samuel Mitchill and Benjamin Rush, telling them that he had been called a “dangerous innovator.” A brief history of the acid/alkali debates of the seventeenth and eighteenth centuries includes information about Otto Tachenius, John Colbatch, Hermann Boerhaave, George Ernst Stahl, William Cullen, Joseph Black, and Antoine Lavoisier. Barker wrote about his experiments, azotic air (nitrogen), and his difficulty understanding the mechanism of this apparently successful therapy. His results were published in the Medical Repository, beginning a correspondence with Samuel Latham Mitchill, professor of chemistry at Columbia University. Contributors to the discussion of alkalis included David Hosack, Thomas Beddoes and James Watt, Humphry Davy, and Matthew Carey. Comments by Charles Rosenberg, John Harley Warner, Lester King, and others help us make sense of medical science and the acid/alkali battle.


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