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The chemical composition of water was discovered about 1784, but when has it been discovered that it is also composed of acid and base?

  • Why do you think this? – Spencer Jun 10 '17 at 22:17
  • Do you mean "that it is also composed of hydroxide and hydronium ions"? Those are not an acid and a base. – Rory Daulton Jun 11 '17 at 00:14
  • @Spencer: ((It is difficult to explain explicitly why I consider acids and bases are crucial in a fundamental sense (you would simply think that it is strange) because it is a discarded and then heavily excluded idea. Responsible for this is this monster here.)) − But consider that the classical neutralization reaction in aqueous solution occurs not by the salt-, but by the water-formation. The components of the salt are only so called spectator ions. –  Jun 11 '17 at 01:24
  • @Rory Daulton: “Those are not an acid and a base.” − The hydrogen ion and the hydroxide ion are very typically ions that act as acid and base in aqueous solutions. Water is not acidic or basic because they neutralize each other. Even the sentence that acid and base form salt, is strictly speaking wrong, since they form water (the salt is only a by-product). –  Jun 11 '17 at 01:26
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    @Zeus, since you mentioned specifically the neutralization reaction, what you seem to be referring to is Arrhenius theory of acids and bases. It was developed in the 1880s and Arrhenius received a Nobel prize for it. Since the early 20th century other people introduced new concepts of acids and bases, e.g. Bronsted-Lowry theory of proton donation and acception. – cesaruliana Jun 11 '17 at 14:18
  • @cesaruliana: Hence, it was not clear before Arrhenius that water is a neutralization product? − Liebig was before Arrhenius …. It is sure that the one who discovered it, communicated it somehow, but perhaps it has been suppressed in those days by Berzelius … –  Jun 11 '17 at 15:35
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    … who was chief of the “Chemical Abstracts” of that time (Jahres-Bericht über die Fortschritte der Chemie und Mineralogie, Laupp’sche Buchhandlung, Tübingen; which appeared yearly, since 1821), and refused to record it? − Because he thought that Liebig’s scientific views are a sign of mental illness, according to unpublished letters of Berzelius (Ostwald, W.: Zur Geschichte der Wissenschaft. Vier Manuskripte aus dem Nachlass von Wilhelm Ostwald, Akademische Verlagsgesellschaft Leipzig, 1985, p. 207). –  Jun 11 '17 at 15:36
  • @Zeus, from what I understand before Arrhenius it was not clear that there was a duality between acids and bases, and that a theory of acids is also a theory of basis. Liebig certainly understood that different acids combine in distinct proportions to substances he called bases, but from my reading of Ladenburg's lectures on the history of the development of chemistry Liebig did not take the neutralization resulting in salts and water as a defining concept of what acids and bases are. Therefore while he knew that water appeared, it was not before Arrhenius it became a central part in theory – cesaruliana Jun 12 '17 at 14:17
  • @cesaruliana: According to E.J. Mills: On Statistical and Dynamical Ideas in Chemistry. – Part I. Acid, Alkali, Salt, and Base. Philos. Mag. 37/251, 461-467 (1869) p. 462, in about 1730 the idea that salts consist of acid and base, was generally accepted. So, your above dictum that “before Arrhenius it was not clear that there was a duality between acids and bases”, seems not to be appropriate. — Liebig defined acids as substances, which release hydrogen when brought together with metals. Since ca 1800 (Davy) it was known that water releases hydrogen with … –  Jun 12 '17 at 21:41
  • … Na (which is also a metal). From Liebig’s definition, it is hence clear (by definition) that water is an acid. But since the resulting solution after this reaction is strongly basic, it follows that it stems from the basic part of water, which the consumed acid (consumed by the metal) has left behind as strong base. Since all this is elemental, one would claim that a man of such geniality as Liebig knew that his acid theory implicitly establishes that water consist of acid and base. — But when he coined this definition in 1838, he had to be prudent how to … –  Jun 12 '17 at 21:41
  • … formulate and interpret it, since {water = acid + base} would have been a too great provocation for Berzelius, who believed that neutralization cannot have something to do with the formation of water. It would have been dangerous for Liebig's scientific career to formulate this explicitly. And later this has been forgotten until Arrhenius, although this discovery is clearly contained already in Liebig’s definition of acid. It has just not been formulated explicitly because of censorship, as is also ubiquitously the case today in science and philosophy. –  Jun 12 '17 at 21:48

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