A manual of qualitative analysis / by Robert Galloway.

  • Galloway, Robert, 1822-1896.
Date:
1858
Catalogue details

Licence: Public Domain Mark

Credit: A manual of qualitative analysis / by Robert Galloway. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    17/216 (page 5)
    passing over the heated liquid, becomes expanded, and would therefore expel the liquid, unless the mouth of the tube was kept firmly closed. 13. If to any salt of ammonia one of the soluble bases is added, the latter will deprive the ammonia of its acid; consequently, the ammonia will be set free, which will be perceived by the smell. The soluble bases set the ammonia free from its salts in the solid state, as well as in solution; heat assists the liberation in each case. If, to any salt of the volatile acids, an acid having a stronger affinity for the base of the salt is added, the volatile acid will be set free; the decomposition takes place as well when the salt of the volatile acid is insoluble as when it is soluble, in water. The following experiments illustrate the principles here stated:— EXERCISES. 14. Dissolve two or three grains of chloride of ammonium in a test-tube containing water; add to it some caustic soda solution, and then warm the liquid in the tube; ammonia will be set free in the gaseous state. It will be known, when it is in the free state, by the smell. 15. Mix two or three grains of dry powdered chloride of am- monium very intimately with a like quantity of slaked lime; place the mixture in a crucible, and warm it by means of a spirit or gas lamp; ammonia will be set free as in the previous experiment. 16. Dissolve a few grains of carbonate of soda in water; add to the solution sulphuric, hydrochloric, or nitric acid—each of these acids deprives the carbonic acid of its base: it is conse- quently set free; and, by its escaping through the water into the atmosphere, causes an effervescence. 17. Place a few grains of chalk or marble at the bottom of a test-tube; cover it with water, and then add to it hydrochloric or nitric acid—either of these acids deprives carbonic acid of its base, consequently it is set free; and, by its evolution, produces