A Manual of the Chemistry of the Carbon Compounds

THE CARBON COMPOUNDS. 165
Normal butyl alcohol is a limpid, mobile liquid, having a vinous
smell, and boiling at 116°.
Butyl Chloride C^HjCl is prepared by saturating the alcohol with
gaseous hydrochloric acid, and heating this solution together with
some concentrated aqueous acid to 100 until the liquid has separated
into two layers, the upper one of which consists of the cliloride. It
is a colourless liquid boiling at 77 O< 6.
Butyl Iodide C^Hgl is best prepared by acting with iodine and
phosphorus on the crude alcohol, and purifying the product hy
fractional distillation; it is a liquid boiling at 129°*6.
Butylamim C4H9.NHji is prepared by heating an alcoholic solution
of butyl chloride with potassium cyanate in sealed tubes to 110°, and
boiling the solution of butyl carbimide thus formed with caustic
potash. It is a limpid liquid, boiling at 75 O# 5, and having great resemblance
in all its properties to ethylamine.
The essential oil of the scurvy-grass (CocJUearia offidnalw) contains
butyl sidphoearbimide VǤ > N, a liquid having a very pungent taste
and smell, and boiling at 160°.
Butyric Add * Vr \ 0 occurs, together with other fatty acids, in
butter, and is also found in the fruit of Gingko Moba, in human
perspiration, in the flesh-juice, and the juice of different beetles. It
is best prepared fioia sugar, which, if old cheese be added to its
aqueous solution, undergoes fermentation by which it is first transformed
into lactic acid, and afterwards into butyric acid. This fermentation
only takes place if the solution remains neutral; chalk
is therefore added to neutralize all the acid formed. The following
proportions answer well:—3 kilograms of oane-sugar and 15 grams
of tartario acid are dissolved in 13 kilograms of boiling water; a
few days afterwards 120 grams of old rotten cheese, which has been
stirred up in 4 kilograms of sour milk, and 1^ kilogram of chalk
are added. The mixture must be kept at a temperature of 30°—35°
for some weeks. After about twenty days the liquid assumes a
paaty consistence, calcium lactato crystallizing out, which soon disappears
again, being converted into calcium butyrate with the simultaneous
evolution of carbon dionide and hydrogen:—>
2Cfifi3« C.HgOj + 2COa + 2Hj
When the fermentation is finished, a solution of 4 kilograms of
crystallized sodium carbonate is added, the liquid is filtered, concentrated
by evaporation, and decomposed by sulphuric acid. Butyric
acid separates as an oily layer, which is dried over calcium chloride
and rectified.
It is a colourless liquid, boiling at 162 s , and possessing a penetrating
sour smell, which in presence of ammonia becomes unpleasant,
like perspiration. It is soluble in water, but separates ogtti n if soluble
salts are added to this solution. Amongst the salts calcium butyrate