Nitrous air

It was as a physicist that Boyle first achieved scientific fame through his studies of the properties of air. He used an improved version of the air pump first constructed by the German physicist Otto von Guericke, and worked with Robert Hooke (1635-1703), who had become his assistant. These studies led to the formulation of Boyle s law (the volume of a gas varies inversely with the pressure), as well as the discovery that air (in contrast to vacuum) is able to propagate sound. He also seems to have realized that air was necessary in order to sustain the life of an animal and the burning of a candle. In his most influential chemical publication, The Sceptical Chymist (1661), he refutes not only the elements of Aristotle (earth, air, fire and water) but also the ideas put forward by Paracelsus that mercury, sulfur and salt were the principles whose proportions in the living organism determined health and disease. 

Instead of the metaphysical (not to say mystical) concept of elements he introduced what he called corpuscles, a kind of elementary particles reminiscent of the atoms of the Greek philosophers Democritus and Epicurus. By thinking in terms of corpuscles and their movements one could understand such properties 

During his short scientific career Mayow published two books. The first, with the title Tractus Duo, was printed in Oxford in 1668 and contains studies of respiration as well as a treatise on rickets. His work on respiration is by far the most important part of the book, and here for the first time he argues that air contains something that he calls nitrous air and alternatively refers to as particulae nitrosalinae and spiritus nitroaereus, which he considers to be necessary 

The concept of phlogiston is often attributed to Georg Ernst Stahl (see above), but he had a predecessor in the German physician, chemist and adventurer Johann 

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Davy s research was to make him famous, not because he performed dangerous experiments, but because he discovered a new recreational drug. In 1800 he published a 580-page book titled Researches, Chemical and Philosophical, Chiefly Concerning Nitrous Oxide, or Dephlogisticated Nitrous Air, and Its Respiration in which he discussed his discovery of, and researches on, laughing gas. Describing its effects, Davy wrote ... 

The conclusions regarding the composition of nitric acid drawn by Lavoisier from these experiments was, that "nitric acid is nothing else than nitrous air, combined with almost its own volume of the purest part of atmospheric air, and a considerable quantity of water."... 

Lavoisier thought of these reactions as the tearing asunder, by mercury, of nitric acid into definite quantities of its three components, themselves distinct substances, nitrous air, water, and oxygen and the combination of the mercury with a certain measurable... 

Dephlogisticated Air term Priestley used for oxygen, air devoid of phlogiston Dephlogisticated Nitrous Air term Priestley used for nitrous oxide, N O, laughing gas... 

The nitrogen dioxide formed dissolves in the water with a consequent shrinkage in the volume of the gases. By repeated trials Priestley established that maximum shrinkage occurred when two volumes of common air were mixed with one volume of nitrous air. When this procedure was tried on air left after combustion had taken place in it, the shrinkage would be less than with common air (some of the oxygen would have been used up) and... 

Priestley s earliest important discovery was that of the gas which he called nitrous air, now known as nitnc... 

The reaction between nitrous air and common air, he then studied in great detail. He collected the nitrous air over water and over mercury, and mixed it with common air in various proportions over water and over mercury. He soon established that the presence of a certain amount of water seemed to produce the greatest contraction of volume. He also found that the greatest amount of reduction in the volume of air so produced was one fifth, and that this reduction could be produced by about one volume of nitrous air to two of air. He then tested the behavior of nitrous air toward common air vitiated, or rendered impure, by combustion, putrefaction, or respiration, and thus found that the purer the air, the greater was the contraction in volume on addition of the fixed volume of nitrous air. 

But what surprised me more than I can well express was, that a candle burned in this air with a remarkably vigorous flame, very much like that enlarged flame with which a candle burns in nitrous air exposed to iron or liver of sulphur (that is, nitrous oxide reduced from nitric oxide, his nitrous air ) but as I have got nothing like this re-... 

Priestley, after his return from the continent in November, 1774, did not take up the more extensive study of the new gas he had obtained from mercurius calcinatus until May 1, 1775. He then found that when tested for purity by his usual test, the nitrous air, that the new gas was much purer than common air, even between five and six times as good as the best common air that I have ever met with. Being now fully satisfied with respect to the nature of this new species of air, viz., that, being capable of taking-more phlogiston from nitrous air, it therefore contains loss... 

In 1772, J. Priestley3 compared the action of fixed air (carbon dioxide) and of nitrous air (nitric oxide) on moist iron, and observed no sensible change with the former gas, but the latter gas was transformed into a species of air in which a candle burned quite naturally, and freely, and which is yet in the highest degree noxious to animals insomuch that they die the moment they are put into it whereas, in general, animals live with very little sensible inconvenience in air in which candles have burned out. He later showed that the candle burns in the new gas with an enlarged flame and that whereas if liver of sulphur be substituted for iron, the conversion of the nitric oxide to the new gas is shortened from 6 to 8 weeks to 24 hrs.—especially if the liver of sulphur be kept warm. He also found... 

H. Davy, Researches Chemical and Philosophical, chiefly concerning Nitrous Oxide or Dephlogisticated Nitrous Air, and its Respiration, London, 1800 G. Kirsch, Zeit. phys. Ghent.,... 

C. Meiner, Recherches sur la decomposition thermique du protoxyde et de Voxyde d azote, Genfeve, 1926 J. Wiswald, Contribution d I etude de la recuperation des gaz nitreux, Genfeve, 1921 H. Davy, Researches Chemical and Philosophical chiefly concerning Nitrous Oxide or Dephlogisticated Nitrous Air, and its Respiration, London, 1800 H. B. Baker, Journ. Ohem. Soc., 65. 611, 1894 Ohem. News, 69. 270, 1894 F. Forster and A. Blich, Zeit. angew. Ohem., 28. 2017, 1910 F. Haber and W. Holwech, Zeit. Elektrochem., 16. 810, 1910. 

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