Page:Scientific Memoirs, Vol. 1 (1837).djvu/177

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obtained by agitating the aqueous solution of hydrospiroilic acid with solution of bromine; it is immediately precipitated in white flocks: the supernatant liquid is colourless, has no smell, and contains hydrobromic acid. In order to free the bromide of spiroil from excess of bromine and hydrospiroil, it must be kept melted in a water-bath so long as acid fumes are given off. Bromide of spiroil is exactly similar to the chloride of spiroil in all its properties; it is quite insoluble in water, and is easily soluble in aether and alcohol. By the spontaneous evaporation of the alcoholic solution it is obtained crystallized; bromide of spiroil melts at a rather higher temperature than the chloride, and like the latter may also be entirely sublimed: when boiled with water it evaporates unaltered. Its behaviour, with regard to the saline bases, is exactly the same as chloride of spiroil, but the alkaline salts are more difficultly soluble: 0.480 grm. bromide of spiroil dissolved in potash and decomposed by nitric acid yielded only 0.02 bromide of silver.

I. 0.510 grm. fused bromide of spiroil yielded

0.690 carbonic acid = 190.78 carbon.
0.510 water =   13.11 hydrogen.

Further, by solution as above-mentioned in pure caustic potash, and combustion of the compound formed, 0.510 grm. bromide of spiroil became 0.485 bromide of silver = to about 0·2036 bromine.

Carbon 190.78   37.41
Hydrogen 13.11 2.57
Oxygen 192.41 20.02
Bromine 203.60 40.00
————  ———
510.00?  100.00

II. 0·325 grm. bromide of spiroil yielded

0.457 grm. carbonic acid = 126.00 carbon.
0.081 ...... water = 8.99 hydrogen.

III. 0·305 grm. bromide of spiroil yielded

0.409 grm. carbonic acid = 113.00 carbon.
0.071 ...... water = 7.88 hydrogen.

If the proportions of bromine in I. be taken, we obtain in 100 parts

I.

Carbon 38.77   37.05
Hydrogen 2.72 2.55
Oxygen 18.51 20.40
Bromine 40.00 40.00
——— ———
100.00 100.00