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but mixes in all proportions with alcohol and ether. It is not affected by
fuming sulphuric acid, but is slowly oxidized by fuming nitric acid, or by a
mixture of nitric and sulphuric acids, when it acquires the odor of Valeriauic
acid. Amyle forms a hydride (C, H U H).

AMYLENE (C 10 H IO ). When amylic alcohol is distilled with anhydrous
phosphoric acid, amylene passes over as a colorless oily liquid. It is lighter
than water; its boiling-point is about 102. It is a hydrocarbon, isomeric
with olefiant gas and etherine ; but the density of its vapor is 5'5, which is
5 times that of olefiant gas ; each volume of it therefore contains 10 volumes
of hydrogen in combination with 10 atoms of carbon. Its vapor has been
used, but unsuccessfully, as a substitute for chloroform in anaesthetic surgery ;
it has caused death iu several instances.



ETHER. ITS PRODUCTION. 595



CHAPTER XLVIII.

ETHER. OIL OF WINE. COMPOUND AND DOUBLE ETHERS.

ETHER (C 4 H 5 0). ETHYLIC OR YINIC ETHER.

THE term Ether is applied to a highly volatile liquid obtained by the
action of sulphuric acid upon alcohol. This liquid is usually procured either
by distilling a mixture of sulphuric acid and alcohol, or by allowing alcohol
to drop gradually into the heated, and somewhat diluted acid.

Sulphuric acid, water, and alcohol, at a certain temperature, are necessary
for the production of ether. Concentrated sulphuric acid mixed with diluted
alcohol, or diluted sulphuric acid mixed with absolute alcohol, will equally
produce ether, provided certain proportions are observed, and a certain
temperature is maintained. The following process has been found to yield
satisfactory results : A mixture of 8 parts by weight of concentrated sul-
phuric acid, and 5 parts of rectified spirit of wine of sp. gr. 0'834, is intro-
duced into a large flask, connected with a proper condensing apparatus and
receiver, and the mixture is heated by means of a lamp until it attains a
temperature of 300. The rectified spirit is then allowed to drop into the
heated mixture through a long funnel, and by adjusting its quantity on the
one hand, and regulating the degree of heat on the other, the temperature
of 300 is maintained as steadily as possible, taking care at the same time
that the liquid in the flask is kept in rapid ebullition. Under these circum-
stances the bulk of this liquid may be maintained unchanged for several
hours, and every drop of alcohol which falls into it is instantly converted
into ether and water, the mixed vapors of which pass through a tu*be into a
condenser. The receiver is ultimately filled with water and ether, the latter
floating upon the former.

The principal point to be attended to in this process, is the maintenance
of a steady temperature at or about 300, and of rapid or even violent ebul-
lition. The limits of the ether-producing temperature are between 260
and 310, and the success of the operation is well insured by the use of oil
of vitriol and spirit of wine, in the above proportions and of the described
strength. If more alcohol, or a weaker acid be used, so as to occasion the
boiling-point to fall below 260, little else than unchanged alcohol distils
over ; and if, by the .employment of too much oil of vitriol, the boiling-point
rises up to or above 320, in place of ether, oil of wine and olefiaut gas are
generated, together with variable quantities of other products.

The proportions recommended by Mitscherlich are, 100 parts of concen-
trated sulphuric acid (which already contains. 18-5 of water) diluted with
20 parts of water, and mixed with anhydrous alcohol, in the proportion of
50 parts to every 100 of concentrated acid. To this mixture heat is ap-
plied, and it is kept boiling until the thermometer within the flask indicates
284 : two strips of paper are then pasted upon opposite sides of the flask
containing the mixture, to indicate exactly the bulk of its contents, by
showing the level of the liquid within it ; alcohol is then allowed to flovv in
by a funnel-tube, the supply being so regulated as to maintain the boiling-
point at 284. The temperature for etherification, according to Mitscher-
lich, is between 284 and 302. The distillate obtained by this process,



596 RECTIFICATION 'OF ETHER. WASHED ETHER.

separates into two parts, the lighter stratum being ether with a little alcohol
and water ; and the heavier, water with a little alcohol, and ether. If the
process has been carefully conducted, the weights of the water and ether
exactly correspond to that of the alcohol consumed. In an experiment on
a large scale, the proportions obtained in the distillate were 65 ether, 18
alcohol, and 17 water. Careful manufacturers obtain from 100 parts of rec-
tified spirit, containing 76 parts, by weight, of absolute alcohol, 60 parts of
ether, of the sp. gr. 0*727 ; according to calculation, they should obtain
58 parts of ether of 0'724.

The ether of commerce almost always contains alcohol, which materially
affects its density ; sometimes it also contains water, which is the case with
what is termed washed ether ; and if ether has been long prepared, it is often
slightly acid, and leaves a peculiar odor when rubbed upon the hand. In
order to procure from the distillate perfectly pure ether, it must be well shaken
in a close vessel with about twice its bulk of water, and allowed to separate
upon the surface of the mixture ; it is then poured off, and a sufficient quan-
tity of well-burned lime added to it, by which the water which it had
acquired by the agitation, is abstracted. The mixture of ether and lime is
then distilled by a water-bath, care being taken to prevent all escape of
vapor, and to keep the condensing-receivers cold : the first third that distils
over may be considered as pure ether, free from alcohol and water. Com-
mercial ether may be purified by agitating it with milk of Ikne, and then
distilling it from a water-bath by a gentle heat ; the first distillate is then
shaken with water to separate alcohol, and the resulting aqueous either sub-
sequently dehydrated by distilling it off quicklime, chloride of calcium, or
anhydrous sulphate of copper.

The chemical changes which take place in the production of ether have
been variously described. The alcohol is entirely resolved into ether and
water (C 4 H 6 2 ==C 4 H 5 0-f HO), but sulphuric acid does not operate by sim-
ply abstracting the elements of water, since ether is equally produced at the
proper temperature (284 to 302) by the reaction of diluted sulphuric acid
on absolute alcohol. One theory assumes that by the admixture of sulphuric
acid and alcohol in certain proportions, Sulphovinic acid is produced ; and
that at a certain temperature, this acid is simply resolved into ether and a
mixture of sulphuric acid and water. Sulphovinic acid has been regarded
by Liebig as a bisulphate of alcohol (C 4 H 6 2 2S0 3 ), and by Regnault as a
bisulphate of ether with 2 atoms of water (C 4 H 5 O,2SO 3 + 2HO). Which-
ever view is adopted, it is obvious that this compound contains all the ele-
ments necessary to the production of ether, when the mixture is exposed to
the temperature required for its decomposition. The researches of Graham
have, however, proved that the production of Sulphovinic acid is not neces-
sary to the formation of ether. When a mixture of oil of vitriol and alcohol
is exposed in a sealed tube to a temperature ranging from 284 to 302, no
charring occurs, but the liquid divides itself into a light stratum which is
nearly pure ether, and a heavy stratum consisting of alcohol, water, and sul-
phuric acid (Journ. Chem. Soc.,'\\\. p. 24). These results confirm the origi-
nal view of Mitscherlich, that alcohol is, under certain fixed conditions,
simply resolved into ether and water by a catalytic, or polymerizing, action
of sulphuric acid. The acid which remains in the retort is unchanged in
properties, and unaltered in quality. A certain proportion of acid is neces-
sary in the process, in order to maintain the liquid in the retort or flask at
the requisite temperature. Sulphuric acid exerts a similar catalytic action
on oil of turpentine : it splits this oil into two other hydrocarbons terebene
andcolophene one of which has a higher boiling point and a greater vapor
density than oil of turpentine. This product, as in the case of ether, does



PROPERTIES OP ETHER. 507

not torm any combination with the acid. As an additional proof that ether
is produced independently of the conversion of alcohol into sulphovinic acid,
it may be stated that the proportions of alcohol and sulphuric acid, which
yield the greatest amount of sulphovinic acid, do not yield the largest pro-
portion of ether. One part of sulphuric acid to 6 or 8 parts of alcohol,
yields the largest quantity of ether and but little sulphovinic acid : the pro-
portion of sulphuric acid must be greatly increased, in order to produce sul-
phovinic acid.

Other acids act in a similar manner. Thus, .when alcohol is heated to a
high temperature with a concentrated solution of phosphoric acid, it is split
into water and ether. In this case the water is retained by the acid, and
when this is sufficiently hydrated, its decomposing action on alcohol ceases.
Certain chlorides and fluorides also produce this conversion. The anhy-
drous chloride of zinc dissolves to a great extent in alcohol. When this
solution is distilled, alcohol first passes over, and as the temperature rises,
ether and water are obtained as products in the receiver.

Properties. Ether is a highly volatile, transparent, colorless, limpid liquid,
of a peculiar penetrating odor, and a pungent and sweetish taste. It is
highly exhilarating, and produces a remarkable species of intoxication when
its vapor is respired mixed with air ; by the proper management of the in-
halation, a continuous insensibility to pain may be maintained. This appli-
cation of ethereal vapor was at one time resorted to in the performance of
surgical operations ; but as an anaesthetic for breathing, the vapor of chlo-
form is now preferred. In the form of a fine spray, ether has been lately
much used as a local anaesthetic. Thus a jet of finely-divided ether directed
against a portion of the skin annuls sensibility so much that severe surgical
operations may be performed without causing pain. Ether is neither acid
nor alkaline ; it has a highly refractive power in regard to light, and is a
non-conductor of electricity. It should not redden litmus when pure. The
evaporation of this liquid produces intense cold. When a few drops of
ether covering a drop of water are blown upon by a blowpipe the water
freezes, in consequence of the rapid evaporation of the ether. The vapor
has been employed for the artificial production of ice on a large scale, the
evaporation of the liquid being accelerated by means of an air pump. In
vacua this liquid boils at the lowest temperature. A mixture of it with
solid carbonic acid causes the thermometer to sink to 166. The sp. gr.
of ether varies greatly with the temperature. We found, at a temperature
of 60, that absolute ether, washed and distilled over quicklime, had a sp.
gr. of 0-713. It is more commonly met with of a sp. gr. of 0*720. This
liquid is so affected in its volume by temperature that 1000 parts at 96 are
reduced to 968'2 at 60, and to 948' at 33.

At mean pressure, ether boils, according to Gay-Lussac, at 96-5. Ether
of the sp. gr. of '720 may be said to boil, under a pressure of 30 inches, at
98. Upon this subject, however, authorities vary a little, in consequence
of variations in the density of the ether, and also of barometical pressure,
circumstances which easily influence the boiling-point of this liquid. Pure
anhydrous ether does not freeze. Faraday failed in congealing this liquid,
although he exposed it to a temperature of 166 below zero. (Phil. Trans.,
1845, p. 158.) The extreme volatility of ether renders it impossible to pour
it from one vessel to another without losing a portion by evaporation, and
its vapor, in consequence of its density, may be seen to fall from the liquid :
it is this which renders it so dangerous to expose ether near to, and espe-
cially above, the flame of a candle. The sp. gr. of the vapor, at mean pres
sure and temperature, is 2'5860 in reference to air as=l. At the tempera-
ture of 21,2, 1 volume of ether gives 212 volumes of vapor. The density ot



598 PROPERTIES OF ETHER.

the vapor may be well shown by dipping a flock of cotton into ether, and
placing it within a glass tube of about an inch diameter, and 18 or 20 inches
long ; the vapor will descend and escape from the lower end of the tube,
where it may be inflamed by a lighted taper, but none rises to the upper end
of the tube. If the lower end of the tube be drawn into a point and bent
upwards, the ether vapor may there be burned in the manner of a gas-light.
The vapor of ether, poured from a wide-mouthed bottle through a long
funnel, will readily fall, and, when ignited, burn at the end of the funnel. If
two or three drachms of ether are placed in a quilled receiver on a stand,
and the vessel is slightly inclined, the ether vapor will fall out of the long
narrow tube, and may be burnt like a jet of gas. Its density is shown by
depressing the tube, when the flame will be much increased. If raised, the
flame is diminished, and ultimately extinguished. This proves the gravi-
tating power of the vapor. The elastic force of the vapor may be shown by
letting a drop or two of ether pass into the vacuum of a barometer, when it
instantly depresses the mercury several inches, more or less according to the
temperature : hence also, when thrown up into gases standing over mercury,
it greatly augments their bulk. The great inflammability of the vapor may
be shown by boiling two or three drachms of ether violently in a Florence
flask, and igniting the vapor as it issues. It burns in a large column of
flame, with a light like that of coal-gas. Ether may be poured upon a large
surface of water, and its vapor burnt on this liquid in a sheet of flame.

When ether is inflamed it burns with a bright and slightly sooty flame,
leaving no residue, and producing carbonic acid and water (C 4 H 5 0-f 120.=
4C0 2 -j-5HO). These products may be collected by holding the mouth of a
clean jar over a flame of burning ether. Water is condensed on the sides of
the jar, and carbonic acid is collected in the interior. When lime-water is
poured into the jar the presence of carbonic acid is proved by the liquid
becoming milky white. Aldehyde and water, as well as acetic acid, are
among the products of combustion at a low temperature (C 4 H 5 O + 20 =
C 4 H 4 O 3 +HO). By passing ether into a jar or bladder supplied with a jet
and stopcock, placed in warm water, its vapor may be burned at the jet.
If its vapor is mixed with about 10 volumes of oxygen, it explodes violently
by an electric spark ; but with smaller quantities of oxygen, or with air, this
combustion is only imperfect. If a little ether is poured into a bladder full
of air, supplied with a stopcock and jet, the mixture of air and ether vapor
may be burned at the jet with a brilliant flame, without risk of explosion.

Exposed to air and light, as in bottles which are frequently opened, ether
absorbs oxygen as strong ozone : it acquires bleaching properties, and is
less capable of dissolving fixed oils. As one of the results of this absorp-
tion of oxygen, acetic acid is produced. The presence of this acid is not at
first apparent, because it forms acetic ether, but it gives to the ether a
peculiar odor, and in time it becomes acid to tests. Ozonized, or, more
correctly, antozonized ether may also be produced by pouring a quantity of
liquid ether into a glass jar, and when the vapor is thoroughly diffused with
air at the mouth of the jar, introducing a bar of iron at a black heat and
moving it about for a short time. The temperature of the metal should not
be sufficiently high to inflame the vapor. Ozone is produced which is readily
detected in the air and escapes with it, while antozone enters into combina-
tion with the ether. Ozone is not soluble in ether, and the name given to
this liquid should therefore be antozonized ether. Besides its bleaching
properties, it oxidizes and destroys offensive effluvia, and is in this respect
a useful deodorizer. It sets free iodine from the iodide of potassium, but it
does not, like ozone, render precipitated guaiacum resin blue. When added
to chromic acid, or to an acid solution of diluted bichromate of, potash, it



PROPERTIES OF ETHER. 59.9

brings ^out a beautiful blue color from the formation of perchromic acid,
which is dissolved by the ether, and this liquid floats with it, forming a blue
stratum on the surface. Ether not containing antozone slowly reduces the
acid chromate, forming green oxide of chromium. The decomposition is
accelerated by heat. Bodies containing ozone only do not produce per-
chromic acid under the circumstances. Another difference has also been
pointed out. It is well known that peroxide of manganese added to an
antozonide causes the evolution of ordinary oxygen, and the properties of
ozonide and antozonide are destroyed. A small quantity of peroxide of
manganese added to what is called ozonized ether, destroys its peculiar
properties, thus proving that it contains antozone, or positive oxygen. Dr.
John Day, of Geelong, Australia, and Dr. B. W. Richardson, have intro-
duced the antozonized ether as a valuable agent in medical practice. Ether
long kept in a bottle containing air generally acquires the properties of an-
tozone. When added to permanganate of potash the pink color is only
slowly discharged by pure and fresh ether; but if it contains antozone the
permanganate is very rapidly deoxodized and loses its color.

If ether vapor is passed over red-hot platinum wire, or if red-hot platinum
wire is plunged into a bottle of air containing a little ether vapor diffused in
it, the metal continues to glow, and acetic and aldehydic acids are produced.
When a stout rod of platinum, copper, iron, or glass, is heated short of
redness, and introduced into the mixture, ozone and antozone are produced
at the expense of a part of the oxygen.

The best method of preserving ether is to keep it in well-stopped bottles,
quite full, and in a dark place. In contact with alkaline bases, this conver-
sion of ether into acetic acid takes place more rapidly. Ether is soluble in
alcohol and chloroform in all its proportions, but has only a limited solubility
in water. Nine parts of water dissolve one part of ether. On this difference
is based the separation of alcohel from ether, as well as the detection of that
liquid in commercial samples. When a mixture of alcohol and ether is
shaken with water the mixture separates into two layers, each of which con-
tains the three liquids. The upper layer contains a large excess of ether,
the lower a large excess of water, with the greater part of the alcohol with
which the ether was mixed. By repeated washing, the whole of the alcohol
may be removed. Ether which has thus been washed retains about a tenth part
of water ; or, according to Liebig, 36 parts of pure ether dissolve one part
of water. From this it may be freed by distillation with quicklime, anhydrous
sulphate of copper or dry chloride of calcium. A mixture of alcohol, ether,
and ethereal oil is known under the name of Hoffmann's anodyne liquor, or
spirit of ether. Such a mixture is employed in photography as a solvent for
pyroxyline.

Ether dissolves a small quantity of sulphur (l-80th), which is not thrown
down by the addition of a little water ; the solution smells of sulphuretted
hydrogen, and by slow evaporation deposits regular crystals of sulphur.
Ether dissolves more than 2 per cent, of phosphorus (l-37th); the solution
when concentrated by evaporation, deposits crystals of phosphorus : it is
luminous in the dark when in contact of air, and if poured upon hot water
produces a brilliant column of luminous vapor. Exposed to air, this solu-
tion becomes acid, and phosphorus is precipitated when it is mixed with
water or alcohol ; vt gradually deposits red phosphorus when exposed to
light. Ether does not dissolve potassa or soda, or their carbonates.

The fixed and volatile oils, many of the resins, caoutchouc, various forms

of extractive, the alkaloids, and some other vegetable principles, are more

or less soluble in ether ; hence ether is often employed in the analysis of

t organic.products, as a means of separating their proximate principles from



600 CONSTITUTION OP ETHER. ETHYLE.

each other. When mixed with chloroform, its solvent power on certain
alkaloids is much increased. Such a mixture is employed as a solvent for
strychnia. Many metallic salts are soluble in ether, and especially the
chlorides of gold, platinum, iron, and uranium ; the property which ether
has of abstracting these salts from their aqueous solutions, has been adverted
to under the history of the respective metals. Potassium and sodium are
converted into potassa and soda by contact with ether, and hydrogen is
disengaged without combustion, the metals floating in the liquid.

A small quantity of sulphuric acid added to ether produces no effect, but
a mixture of equal parts of ether and the acid blackens, and yields, on dis-
tillation, oil of wine, olefiant gas, acetic and sulphurous acids, and water ; it
leaves a resinous matter and charcoal. Anhydrous sulphuric acid decom-
poses ether, and produces, according to Liebig, " isethionic and althionic
acids, oil of wine, and sulphate and bisulphate of oxide of ethyle ; if heat
be used, these products are decomposed, and sulphate of oxide of ethyle, oil
of wine, water, and ether, together with acetic, formic, and sulphurous acids,
carbonic oxide, and olefiant gas, pass over." Heated with nitric acid, ether
yields, according to Liebig, carbonate, acetic, formic, and oxalic acids, as
well as aldehyde.

When a little ether is introduced into chlorine, the gas is absorbed, and
peculiar compounds result. When bubbles of chlorine are passed into ether,
they often cause inflammation, and when a small quantity of ether is poured
into a jar of gaseous chlorine, and a lighted taper is applied, hydrochloric
acid is formed, and carbon is set free, sometimes with explosion. Iodine
and bromine are soluble in ether, and gradually react upon and decompose
it. The solution of iodine in ether is dark brown, and soon gives rise to
the production of hydriodic acid. When ether is saturated with bromine,
and the mixture is left for ten or twelve days, it is entirely decomposed ; the
products are, 1, formic acid(?); 2, hydrobromic acid ; 3, hydrobromic ether;
4, heavy bromic ether ; 5, bromal. The first four products may be separated
by distillation, and the bromal remains (C 4 HO a Br 3 ) : it may be purified by
mixture with water, and in the course of twenty-four hours crystals of hy-
drate of bromal are formed. When this hydrate is boiled with an alkaline
solution, 2 atoms are resolved into 2 atoms of formic acid, 2 of bromoform,
and 6 of water.

Composition. The vapor of ether, when passed through a red-hot tube,
is decomposed : carbon is deposited, and water and aldehyde are among the
products. When the vapor is analyzed by passing it through red-hot oxide
of copper, the results furnish the following elementary composition :

Atoms. Weights. Per cent. Vols. Sp. gr.

Carbon . . . 4 ... 24 ... 64-87 ... 4 ... 1-6584

Hydrogen . . . 5 ... 5 ... 13-51 ... 5 ... -0-3455

Oxygen . . . 1 ... 8 ... 21-62 ... g ... 0-5528

Ether ... 1 37 100-00 1 2-5567

The specific gravity of ether vapor compared with air is 2-5573, and its
calculated density is in accordance with this result. Compared with hydro-
gen, the sp. gr. of ether vapor is 37 ; its volume equivalent is 1. If oxygen
is assumed to be 16, the equivalent of ether must be doubled. Its relations
to alcohol and other bodies would thus be disturbed, and the formula for the
various ethers would be rendered unnecessarily complex.

Tests. Ether may be identified by its odor and inflammability, as well as
by the color of its flame and the products of combustion.

Ethyle. Ether is commonly regarded as an oxide of the compound radical
Ethyle (C 4 H 5 ). With an atom of water it forms alcohol, which is therefore a.



HEAVY OIL OP WINE. NITRIC ETHER. 601

hydrated oxide of etbyle. Ethyle combines with the halogens and ether, as
its oxide combines with the oxacids. Dr. Frankland isolated this radical
by the action of zinc on iodide of ethyle. (Journ. of Ckem. Sci., ii. p. 263.)



Online LibraryWilliam Thomas BrandeChemistry → online text (page 91 of 124)