It follows from what has been stated of the mode in which oleic acid is procured, that it enters largely into the composition of soaps, forming with potash soft soap, and with soda hard soap.
The Oleates in general are not crystallisable salts ; and those which are not altogether insoluble are mucilaginous before drying ; they-are usually very fusible.
Oleate of Potash.—This salt has a bitter alkaline taste. When mixed with twice its weight of water, it swells and forms a trans parent jelly ; when this quantity of water is doubled, a syrupy liquor is obtained. A still larger quantity of water does not render it turbid, but after a considerable time a mucilaginous superoleate of potash separates. Alcohol dissolves its own weight of oleate of potash, when heated to l21* Fahr. and it solidifies on cooling; 100 parts of boiling ether dissolve 3.43 parts, and the solution remains fluid when cold.
Pi-oleate of Potash may also be formed; it is soluble in water and in alcohol both hot and cold, and the solution reddens litmus.
Oleate of Soda—Has a slight smell, and a slightly alkaline taste: Cold water dissolves 1-10th of its weight.
Oleate of Baryta is insipid, and insoluble in water. Boiling alcohol dissolves only a small quantity. It is soluble in oleic acid.
Oleate of Magnesia—llas the form of semi-translucent white grains, which soften between the fingers.
Oleate of Copper.—This salt is green. It melts when exposed to tho heat of the sun.
Oleate of kead.—The neutral oleate is prepared in the moist way. It melts between 144° and 153° Fahr. Alcohol andether dissolve it slowly when cold and rapidly when hot, without altering its neu trality.
Superoleate of Lead.—This salt is liquid at 75° Fahr., and below this temperature becomes an adhesive mass. Boiling alcohol dissolves a little of it, and deposits a neutral salt on cooling. Oil of turpentine and oil of petroleum dissolve both it and the neutral oleate.
Oleate of Methyl has a specific gravity of 0.879 at Fahr.
Oleate of Ethyl or oleic ether is formed on passing a rapid current of hydrochloric acid gas into a solution of oleic acid in three times its bulk of alcohol. It is colourless, very soluble in alcohol, and has a specific gravity at 65° Fahr.
Sulpholcie Acid occurs among the products of the action of concentrated sulphuric acid upon olein ; cold water decomposes a part of it with production of metaoleic acid, and the remainder on boiling is converted into hydroleic acid.
Chloroleic Acid is produced by the action of chlorine upon oleic acid. It is liquid at ordinary temperatures, has a brown tint and ap. gr. P082 at 46° Fehr. Its boiling point is 374° Fehr.
Bromoleic acid much resembles chloroleic acid. Its sp. gr. is P272 ; boiling point 392° Fahr.
Elaidic Acid bears the same relation to oleic acid that elaidin does to olein ; it may in fact simply be considered as a solid modificatidn of oleic acid. It is produced, or rather induced, by the presence of a small quantity of peroxide of nitrogen. The oleic acid operated upon neither changes its composition nor its atomic weight ; a small quantity is however acted upon, as traces of an oily body and of ammonia are generated, and it is not improbable that these communicate molecular motion to the particles of the oleic acid.
Elaidic acid melts at about 1]3° Fahr. It is soluble in ether or alcohol, tend by spontaneous evaporation is deposited in beautiful pearly scalds resembling benzoic acid. It is volatile, and may be distilled with but little alteration. Maintained at 150° Fehr. for some time it absorbs oxygen, acquires a rliengresable rancid odour, ia con verted into a and is no longer solidiflablo by peroxide of nitrogen. Like o ele acid, it jichis pelmitie and acetic acid when fused with hydrate of potash.
F-Isidie acid is of comae produced when oleic acid or olive oil is acted upon by nitric acid or ultrate of mercury, the ultimate products of the action of excess of strong nitric acid are, however, acetic, acid, pi-epistle acid. butyric acid and the whole of the associated achln of the homologous aeries CulluO„ up to esprit acid Inclusive; as well an four tsrtns of the dibasic acid scrim, namely, subcric, alipic and lip4c acids.
The et,idates have the same competition as the eloates. Those of the alkalies crystallise, snnd are soluble in water. Etaidaic of ulcer is a white voluminous precipitate containing (C,11,040.). Elaidatc of methyl has the composition LIaldate of ethyl or elaidic rarer (C,I1(C,II.)0,,) is a colottrlees, morloroue, tasteless oil of sp. gr. 0.963 at 65* Fehr. Boiling point about 590° Fehr.