For illuminating purposes, the most extensively-used product is kerosene, but both the more and the less volatile portions Of petroleum are employed in suitable lamps.
Difficultly volatile liquids may be weighed directly into the boat; volatile liquids are weighed in thin hermetically sealed bulbs, the necks of which are broken just before they are placed in the combustion tube.
==Pharmacology, Toxicology and Therapeutics of Alcohol== Alcohol is of great medicinal value as a solvent, being used to form solutions of alkaloids, resins, volatile oils, iodoform, &c. In strength of about 10% and upwards it is an antiseptic. If applied to the skin it rapidly evaporates, thereby cooling the skin and diminishing the amount of sweat excreted.
This may be due in some measure to the small number of gaseous and easily volatile substances then known, to the attention which the study of the organic compounds received, and especially to the energetic investigations of J.
If it possesses an alkaline or acid reaction, it must be tested in the first case for ammonia, and in the second case for a volatile acid, such as sulphuric, nitric, hydrochloric, &c.
Both forms are volatile in steam.
Crop yields are highly volatile and unpredictably so.
It is a species of cannel coal, somewhat similar to the Boghead mineral of Scotland, but yielding a much larger percentage of volatile hydro-carbon than the Scottish mineral.
They contain a volatile oil which does not occur in the corm, and their proportion of colchicine is higher, for which reason the Tinctura Colchici Seminum- dose 5 to 15 minims - is preferable to the wine prepared from the corm.
Buchu leaves contain a volatile oil, which is of a dark yellow colour, and deposits a form of camphor on exposure to air, a liquid hydro-carbon being the solvent of the camphor within the oil-glands.
The drug has the properties common to all substances that contain a volatile oil.
Similarly it is necessary, in view of the hydrostatical relations of water and mineral oils, and the volatile character of the latter, that the porous stratum should be protected from water and air by an overlying shale or other impervious deposit.
Journ., 1811, 8, p. 302), and obtained by the action of chlorine or sodium hypochlorite on ammonium chloride, or by the electrolysis of ammonium chloride solution, is a very volatile yellow oil.
If we take a thin layer of natural Canada balsam and heat it strongly for a little time most of the volatile oils are driven out of it.
The lower members of the series are neutral liquids possessing a characteristic smell; they are soluble in water and are readily volatile (formaldehyde, however, is a gas at ordinary temperatures).
The German consul at Pretoria at this j uncture as a volatile, sanguine man, with visionary ideas of the important part Germany was to play in the future as the patron and ally of the South African Republic, and of the extent to which the Bismarckian policy might go in abetting an anti-British campaign.
ETHER, (C 2 H 5) 2 O, the Aether of pharmacy, a colourless, volatile, highly inflammable liquid, of specific gravity o 736 at 0°, boiling-point 35° C., and freezing-point 117 0.4 C. (K.
It has a strong and characteristic odour, and a hot sweetish taste, is soluble in ten parts of water, and in all proportions in alcohol, and dissolves bromine, iodine, and, in small quantities, sulphur and phosphorus, also the volatile oils, most fatty and resinous substances, guncotton, caoutchouc and certain of the vegetable alkaloids.
Fermentative changes are set up in it, characterized by the evolution of gas and the formation of products of suboxidation, some of which, being volatile, account for the characteristic odour.
Practically non-volatile: (copper), iron, nickel, cobalt, aluminium; also lithium, barium, strontium and calcium.
Of the several individual chlorides, the following are liquids or solids, volatile enough to be distilled from glass vessels: AsC13, SbC1 3, SnCl 4, BiCl 3, HgC1 2, the chlorides of arsenic, antimony, tin, bismuth, mercury respectively.
The following, though volatile at higher temperatures, are not volatilized at dull redness: KC1, NaCI, LiC1, NiC1 2, CoC1 2, MnC1 2, ZnCl 2, MgCl 2, PbCl 2, AgCI, the chlorides of potassium, sodium, lithium, nickel, cobalt, manganese, zinc, magnesium, lead, silver.
Somewhat less volatile than the last-named group are the chlorides (MC1 2) of barium, strontium and calcium.
The light oil fraction of the coal-tar distillate, which comes over below 140° and consists principally of benzene, toluene and the xylenes, yields on fractionation (i) various volatile impurities such as carbon disulphide, (2) the benzene fraction boiling at about 80° C., (3) the toluene fraction boiling at too°, (4) the xylene fraction boiling at 140°.
There is also present a volatile oil.
The ore, even if it is not blende, must be roasted or calcined in order to remove all volatile components as completely as possible, because these, if allowed to remain, would carry away a large proportion of the zinc vapour during the distillation.
The less volatile vapours are condensed and return to the flask,, while the more volatile component passes over.
The success of the operation depends upon two factors: (I) that the heating be careful, slow and steady, and (2) that the column attached to the flask be efficient to sort out, as it were, the most volatile vapour.
Three types of columns are employed: (I) the elongation is simply a straight or bulb tube; (2) the column, properly termed a "dephlegmator," is so constructed that the vapours have to traverse a column of previously condensed vapour; (3) the column is encircled by a jacket through which a liquid circulates at the same temperature as the boiling-point of the most volatile component.
Although, as is generally the case, one liquid (say A) is more volatile than the other (say B), i.e.
P 1 greater than P2, if the molecular weight of A be much less than that of B, then it is obvious that the ratio M 1 P 1 /M 2 P 2 need not be very great, and hence the less volatile liquid B would come over in fair amount.
With difficulty volatile substances, e.g.
The vapours rising from the still traverse a tall vertical column, and are then conveyed through a series of bulbs placed in a bath kept at the boiling-point of the most volatile constituent.
The more volatile vapours pass over to the condensing plant, while the less volatile ones condense in the bulbs and are returned to the column at varying heights by means of connecting tubes.
Above this "separator" is a reflux condenser, termed the "cooler," maintained at the correct temperature so that only the more volatile component passes to the receiver.
The first portion of the distillate brings over the gases dissolved in the water, ammonia and other volatile impurities, and is consequently rejected; scarcely two-fifths of the entire quantity of water can be safely used as pure distilled water.
Mansfield (1819-1855), who separated a benzol distilling below too from a less volatile naphtha by using a simple dephlegmator.
Most of the polynitro compounds are not volatile, but undergo deco Imposition on heating.
It is found in the volatile oils of Spiraea, and can be obtained by the oxidation of the glucoside salicin, (C13H1807), which is found in willow bark.
It is volatile (para-oxybenzaldehyde is not) and gives a violet coloration with ferric chloride.
When this volatile liquid hydrocarbon (isoprene) is allowed ro stand for some time in a closed bottle, it gradually passes into a substance having the principal properties of natural caoutchouc. The same change of isoprene into caoutchouc may also be effected by the action of certain chemical agents.
It is somewhat volatile at ordinary temperature, and its aqueous solution possesses a strongly acid reaction.