Nice To His Mice

In the landmark 1772 paper Priestley describes the isolation and properties of gases first observed by others but not so systematically. He described carbon dioxide ( fixed air —sometimes termed mephitic air), nitrogen (the air remaining after a candle had burned out in common air and following CO2 precipitation in lime water—he termed it phlogisticated air, often also termed by others mephitic air ), hydrogen (Cavendish s inflammable air —sometimes confused by Priestley with carbon monoxide), hydrogen chloride ( acid air —later marine air ), and nitric oxide (NO— nitrous air ). 

part d, and also Fig. 3) depicts an experimental mouse, Partington notes that Priestley always took pains to keep his mice warm and comfortable.  

The Development of Modern Chemistry, Harper Row, New York, 1964. pp. 40-50. 

This figure is from the 1790 edition (Experiments and Observations on Different Kinds of Air and other Branches of Natural Philosophy, three volumes, Birmingham, 1790) of the six books published between 1774 and 1786. The same figure appeared in Volume 1 of that series. 

It is important to note that nitric acid is different from an acid such as hydrochloric in that the nitrate part (NQj is a stronger oxidizing agent than aqueous hydronium ions (H3O ). Thus, copper and iron, which have more positive (more favorable) reduction potentials than H3O, are not oxidized readily in HCl to produce Hz gas. However, they are oxidized by the powerful NO3, which has a very high reduction potential and is therefore readily reduced to NO. Magnesium, which is very easily oxidized (very hard to reduce), will produce H gas in both hydrochloric and nitric acids. 

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