Compound with H2O. Terpin C10H182HO is formed when 1 volume of spirits of turpentine is mixed with 6 of nitric acid and 1 of alcohol, and exposed to air for some weeks. Crystals are formed which are pressed, decolorized by animal charcoal, and recrystallized from boiling water.
Compounds with HCl. When a slow current of HCl is passed through cooled spirits of turpentine, two isomeric compounds are formed, one solid, and one liquid. The lower the temperature is kept, the more of the solid body is produced. To obtain the solid body pure it is pressed and recrystallized from ether or alcohol. It is volatile and has the odor of camphor. It is called artificial camphor, and has the composition C10H16HCl. There is also a compound with 2HCl.
Oxidation products. By passing air into spirits of turpentine oxygen is absorbed. It was thought at one time that ozone was produced, but Kingzett's view is that camphoric peroxide is formed C10H14O4, and that in presence of water it decomposes into camphoric acid and H2O2. This liquid constitutes the disinfectant known as "sanitas," which possesses the advantages of a pleasant smell and non-poisonous properties. C10H18O2 may be obtained by exposing spirits of turpentine in a flask full of oxygen with a little water.
Camphor C16H16O has been made in small quantity by oxidizing spirits of turpentine. Terebenthene belongs to the benzene or aromatic series, which can be shown from its connection with cymene. Cymene is methylpropyl-benzene, and can be made from terpenes by removing two atoms of H. It has not yet been converted again into terpene, but the connection is sufficiently proved. The presence of CH3 in terpenes is shown by their yielding chloroform when distilled with bleaching powder and water. The resin is imperfectly known. It was supposed to consist of picric and sylvic acids. It is also stated to contain abietic anhydride C44H62O4, but it is difficult to understand how a compound containing C44 can be produced from C10H16. The most probable view is that it is the anhydride of sylvic acid, which is probably C20H30O2.
The dark colored resin which is obtained when the turpentine is distilled without water can be converted into a transparent slightly yellow body by distillation with superheated steam. A small portion is decomposed, but the greater part distills unchanged. It is used in making soap which will lather with sea water.
When distilled alone, various hydrocarbons, resin oil and resin pitch, are obtained.
I find that commercial spirits of turpentine varies in sp. gr. from 0.865 to 0.869 at 15° C. The higher sp. gr. appears to be connected with the presence of resinous bodies, the result of oxidation. The boiling point is very uniform, ranging from 155° C. to 157° C. at 760 mm. Taking these two points together, it is hardly possible to adulterate spirits of turpentine without detection. I give the figures for a few imitations or adulterations:
| Sp. gr. | B.P. | |
| No. 1 | 0.821 | 137° C. |
| No. 2 | 0.884 | 165° C. |
| No. 3 | 0.815 | 150° C. |
| No. 4 | 0.895 | 156° C. |
There is a considerable difference in the flashing point, no doubt due to the longer or shorter exposure of the crude turpentine, by which more or less of the volatile portion escapes.