The student's chemical pocket companion / by W. S. Jacobs, M.D.

  • Jacobs, William Stephen, 1770-1843.
Date:
1807
Catalogue details

Licence: Public Domain Mark

Credit: The student's chemical pocket companion / by W. S. Jacobs, M.D. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    [ 120] hydrogen, which holds the sulphur in solu- tion, forming water on coming in contact with the oxygenous portion of the atmos- phere ; and the sulphur is precipitated. The sulphur of hepatic gas may be pre- cipitated by very strong nitric acid. Arse- nic also detects the sulphur: and the ace- tite of lead forms a brownish precipitate. IN METALLIC WATERS, The gallic acid strikes a back colour with the iron in the water ; the prussiate of potash and lime produces a blue one. When the carbonic acid holds iron in solution in mineral Maters, it may be driven off, by boiling, and the iron falls to the bottom, in the state of an oxyde. Sulphate of copper is detected by the volatile alkali, forming the cuprum ammo- niacum. By immersing a piece of polished iron in it, the acid unites to the iron and the copper is precipitated on it. Arsenic is detected by adding the cuprum ammoniacum, forming a greenish yellow precipitate, or by evaporating the water, and exposing the residue on burning coals, the smell of garlic will be evident. The residuum of evaporation may also be placed between two pieces of copper, and exposed to heat: the surface of the copper will become white.