John Almon.

The American journal of science and arts online

. (page 63 of 102)
Online LibraryJohn AlmonThe American journal of science and arts → online text (page 63 of 102)
Font size
QR-code for this ebook

some new mixed acids which he has produced. Reasoning from the well
known fact that by the action of potassic hydrate upon monobromacetic
acid, glycollic acid is formed, according to the equation

(or, as is more clearly exhibited in Frankland's notation,


the change being the substitution of Ho(=:HO, hydryl) for Br, — Gkl
concluded that the similar univalent radical oxacetyl,* in potassic acetate^
might be similarly exchanged. Though in the discovery of such mixed
acids, Oal has been anticipated by Strecker, Wurtz and others, he has in
the present research added several new ones to the list.

By heating to 100^ C. in a sealed tube, an alcoholic solution of ethylic
monobromacetate with potassic acetate, he obtained a liquid having a
density about 1, whose boiling point was 180^ C, and whose formula, aa
given bv analysis, was "S^H ^ ^O^. When heated in a sealed tube with an
alcoholic solution of potassic hydrate, it was decomposed, yielding potassio
acetate and glycollate, and alcohol. If it be treated with solid potaah,
and distilled, acetic ether passes over, and potassic glycollate remains in
the retort From these reactions, Gal infers that th^ liquid above men-
tioned is the ether of an acid formed from glycollic acid by replacing ita
hydryl by the radical oxacetyl, and which he calls aceto-glycollic acid. Its

formation is thus represented : | gg|B'+ 1 ^^- ] J||^~+KBr.
* Oxacetyl, Aoos^^aHjO,).

Digitized by


Chemistry and Physics. 105

By alcoholic potash it breaks up thus :

{SIC-HHH.),= fg?lg» + {S|t,+ iSg;Ho.

B,»uap«t«k„Mo«: )g|C+™»=iolfe?=|oek>.

The ordinary compouod ethers when distilled with potash, produce alco-
hol, and a salt of the acid they contain ; while these mixed-acid ethers
yield either a salt and a more simple ether ; or two salts and alcohol.

This view of its constitution, Gal proposed to confirm by submitting
the new ether to the action of the hydracids according to the method
given in the preceding section. He saturated therefore several grams
of this aceto-glycoUic ether with hydrobromic acid . ffas, and heated to
100^ G. After repeating this process several times, tne product was dis-
tilled on the water bath. The distillate was pure ethylic bromid. A
viscous mass was left in the retort which upon examination proved to be
a mixture of acetic and monobromacetic acids ; the action of the hydra*

in perfect accordance with the generalization above given.

Gal prepared also ethylic butyro-glycollate, -J n^^ > ^7 treating
potassic butyrate with ethylic monobromacetate ; ethylic butyro-butyl-
lactate (better butyro-oxybutyrate), •< q^^i^ ; and ethylic aceto-oxy-

butyrate ] nry^^ ^- The last is isomeric with butyro-glycollic ether,

both containing ^^Hj^O., The number of mixed acids which can
thus be formed is, as Gal observes, very great ; especially when not only
the mono-brominated fatty acids, but also the di- and tribrominated bod-
ies of this series are used as starting-points. — Bull, Soc. Ch,y II, vii, 329,
April, 1861

5. On some new compounds of silicon, — In a series of researches upon
silicon and its compounds, made some years ago by Wdhler and Buff,
they obtained, by passing hydrochloric acid gas over crystallized silicon
heated to a temperature just below redness, a very volatile liquid, boiling
at 42^ C. and yielding an inflammable vapor. This liquid was decomposed
by water, with the production of a white substance, differing entirely
from silica in its properties. To the volatile liquid these chemists gave
the formula Si2Cl3-|-2HCl ; and to the white body the corresponding for-
mula SigO j-|-2H0, (Si=:21).* More recently, however, Wohler assio^n-
ed to these bodies the formulae SigH^Ol^Q and Si^H^O^Q respectivelyf
(8i=:14.) The authors observe that the above compounds may not have
been absolutely pure when analyzed, and call upon chemists having more
leisure to re-examine the whole subject.

This investigation has been undertaken by Friedel and Ladenburg.
In the first place, they thought it improbable from theoretical considera-
tions, that so volatile a body as the above chlorid should have so compli-
cated a molecule; and from its method of preparation they inferred that

* Ann. Oh. Fharm^ dv, 94. This Journal, 11, zxv, 270, 1868.
t lb., czxvii, 267. This Journal, IC, zzzvii, 120, 1864.
Am. Joub. Sol— SacoRD Sasns, YoIh XLIV, No. 180.— July, 1867.

Digitized by


106 Scient^ IrUettigence.

it might be Bilicic ohiorid, in which aa atom of hydrc^^^n had replaced
one of chlorine. If they could not separate the body in question from the
silicic chlorid formed at the same time, by fractional distillation, they
were prepared to convert both into ethers and thus to effect the separation^

The compound was prepared by Wohler and Buff's method. And
they found that by subjecting the crude material to a series of careful
fractionings, a liquid was obtained whose boiling point was 34** C. in-
stead of 42*", and which distilled entirely between 34^ C. and 37*5**. Aa
thus purified, the liquid posseBsed all the properties mentioned by Wohler
and Duff. Its vapor mixed with air detonated violently in contact with
flame, giving a white doud of silica. It was analyst by placing a
weighed quantity in a sealed bulb, introducing this into a tube contain-
ing dilute ammonia, sealing the tube, and breaking the bulb. After a
short time the tube was opened, its contents poured into a platinum dish
and evaporated to dryness on Uie water-bath. The residue was treated
with water, filtered, ignited and weighed ; and by subtracting from the
entire weight, that of the glass of the bulb, that of the silica was obtain-
ed. In &e filtrate the chlorine was determined as usual. The results
lead to the formula SiClgH, (Si=28.) That this formula moreover, rep^
resents the size of the molecule was proved by the vapor density ; exper-
iment giving 4*64, while theory requires 4*69. The hypothesis of its
composition is thus confirmed ; and they showed farther that at ordinary
temperatures chlorine transforms it into silicic chlorid, 8i01^ ; while at a
red heat hydrogen acts upon SiOl^, converting a portion of it into BiClgH.

When this substance is mixed with absolute alcohol, a large quantity
of hydrochloric acid ^as is evolved, and the resulting liquid, when sub-
jected to fractional distillation, yields two bodies, one of which boils
between 134*^ and 137% and the other at led"" C. The latter body is
silicic ether ; the former is an ether corresponding to the chlorid above
described. Its analysis gives the formula SiO^H. .Og, from which the

authors derive the constitutional formula A '^ \ r ^s* When silicic

chlorid SiOl^ acts upon alcohol, it produces silicic ether /f« n ^ i ^«'

as is well known ; consequently the new ether bears the same relation to
the volatile chlorid, that silicic ether bears to silicic chlorid. It is a
limpid liquid, with an agreeable odor, and insoluble in water, by which it
is slowly decomposed. It is rather more inflammable than silicic ether,
and differs from it by evolving hydrogen when treated with an alcohdic
solution of ammonia.

The action of sodium upon this ether is quite remarkable. When first
introduced, a slight evolution of gas is perceived, due probably to the
trace of alcohol present, produced by the action of atmospheric moisture
on the chlorid. But if tne mixture be gently heated, there is a uniform
evolution of gas which upon examination proved to be pure hydric silicid
or siliciuretted hydrogen. After allowing the first portions of the gas
to escape, it may be collected for analysis. This was effected by placing
a measured quantity in a graduated bell over mercury, and then passing
up a concentrated solution of potash. The evolution of gas commenced
at once ; and, when the action ceased the volume was measured. It was
found to occupy four times the volume of the original gas, and to bum

Digitized by


Chemistry and Physics. 107

with ihe pale flAme charaoteristic of hydrogen. The action of the pot-
ash then is as foUows : (HX0)44.&iH. zTrK^Sie^+Hg,
from which it appears that one half the hydrogen comes from the potas-
sic hydrate, the other half from the silicid. As 2 vols.* of the latter in-
crease to 8 vols, in the above experiment, they evidently furnish 4 vols,
of hydrogen ; and since an atom of hydrogen occupies one volume, and
a molecule of silicid 2 volumes, it is evident that eaeh molecule of the
latter contains 4 hydrogen atoms, and that its formula is SiH^. This is
the formula assigned to it by Wdhler and 6uf^ its original discoverers ;
though they never obtained it pure, but always mixed with free hydrogen.
The liquid which results from the action of the sodium, is pure ethylie
dlioate. The sodium appears to take no part in the reaction, since it re-
mains white and metallic, and does not diminish in weight The forma-
tion of the hydric silicid may therefore be thus represented :

((t?;:h.).=«M(«.H.^ !«.).■

The gas thus obtained is not spontaneously inflammable, at the ordinary
atmospheric temperature and pressure. But if into a small quantity of
it confined in a tall jar over mercury, — so that the mercury column consid-
orably lessens the pressure, — a few bubbles of air be passed, ignition takes
place with deposition of silicon mixed with silica. In this respect the
^as behaves like hydric phosphid ; and the authors suggest that the hy-
drogen mixed with the SiH^ of Wdhler and Buff, may oe the cause of its
spontaneous inflammability. A hot knife blade placed near the bubbles
as they rise through the mercury, inflames them with a slight explosion.
Friedel and Ladenburg have also examined the white substance pro-
duced by the action of water on the inflammable chlorid. It was pre-
pared by passing the vapor of this chlorid into water at zero. The pro-
duct was washed with ice-cold water, dried, first in a vacuum over sul-
phuric acid, and then in an oil bath at 150° to 180° 0. and ansdyied.
The results give the formula Si2H208t from which the authors derive

the rational formula a:]^^ f ^' ^^ production is expressed thus :

((9iH)ci,),+(H,e),=|g| I e+(HCl)e.

These researches confirm the opinion originally advanced by WShler
that these compounds are analogous to organic bodies, and consequently
prove the analogy of silicon and carbon. It will be noticed that the in-
flammable chlorid (SiH)0l3 is similar to chloroform (€E[)Cl3 ; that the

compound^ J -rr { (Oacorrespondsprecisely to the tribasic formic ether
of Kay /r) u \ r ^s ; ^^t hydric silicid SiH^, is analogous to hydrio

oarbid €H^ ; and that the body ain^ j- O is identical in structure with

€/HO )
formic anhydrid ^^^ \ O. For this reason, Friedel and Ladenbuig

propose the name sUiei^hloroform for the first substance, tribasic silicic
formic ether for the second, and silid-formic anhydrid for the last. The
quadrivalence of silicon seems therefore as firmly established as that of
carbon \\x^M—Bull Soe. Ch., 11, vii, 322, April, 1867.

Digitized by


106 Scientific Intelligence.

6. OrysUdlization of ffraphiUndal silicon. — Profeeaor W. H. Miller
has examined some crystals of graphitoidal silicon, so called, which were
received from Dr. Percy. They appeared to be oblique ; but on meas-
urement, they were found to be regular octahedrons, in which two par-
allel faces were much larger than the others ; two other parallel fooes
were either too small to be obsenred or were altogether wanting. One of
these scales had the faces of a twin octahedron. He concludes therefore,
that there is no crystalloffraphio reason for separating the graphitoidal
from the ordinary octahedral variety of silicon.

He also considers it probable that graphitoidal boron, recently shown by
Wdhler and Deville to be an aluminic bond, is tetragonal, as Sella has
shown the adamantine boron to be. Sella views even the latter variety
as a definite compound of boron with aluminum and carbon, mechan-
ically mixed with pure boron. — PkU, Mag., IV, xxxi, 807, May, 1866.

7. Dennty of Ozone. — At the meeting of the French Academy on the
6th of May, Rxonault communicated a note from Soret of Geneva, npon
the density of ozone. As previously determined by this chemist, the den-
sity of this substance obtained in absorption experiments, is one and a half
times that of oxygen. He has now re-deternained it by means of Graham's
law of diffusion ; i. e., the velocity of diffusion of a gas is inversely as the
square root of its density. He ascertained the coefficient of diffusion of
chlorine into oxygen and of ozone into oxygen. He found that in 45
minutes, for every cubic centimeter of chlorine contained in one of the
two diffusion tubes, 0*227 of chlorine diffused into the upper tube, while
for ozone, the quantity under the same circumstances was 0*271. Now
the ratio *227 : 27l='8382: 1 ; and if we assume ozone to have one
an d a h alf times the density of oxygen, Graham's law would give us
V^35'5 : V^24=:l : '8222, a remarkably close approximation, considering
the difficulties of the method. We may therefore fairly regard the den-
sity of ozone as one and a half times that of oxygen ; or 1*657 if air be
taken as 1, and 24 if hydrogen be unity. While therefore the molecule
of free oxygen contains two atoms, that of ozone contains three. — The
Laboratory, i, 121, May 18, 1867.

9. Adamantine anthracitic carbon. — In the name of M. le Ck>mte de
Douhet, Dumas presented recently to the Academy of Sciences at Paris
some nodules of mineral carbon, remarkable for their hardness. They
were found by Douhet in the hands of a merchant, who supposed them
to come from Brazil, but their origin and mode of occurrence are not
certainly known. These nodules consist of irregularly concentric layers.
When cut and polished on the lapidary's wheel, they acquire a surpris-
ing luster. Even in the thinnest fragments the mineral is opaque. Its
density is 1*66. A preliminary analysis by Friedel showed the presence of
11 percent of ash; thus raising the question whether the hardness is
not due to foi*eign impurities. Dumas therefore examined purer frag-
ments, and found the quantity of ash 4 per cent in two specimens ; one
being the crude material, the other the same after pulverization and wash-
ing. Hence the ash is uniformly distributed through the mass. More-
over this ash is neutral in its reactions, and neither scratches nor abrades
glass. Two elementary analyses gave Dumas, as a mean, the following
composition: carbon 97*5, hydrogen 0*5, oxygen 1*5, ash 0*5=100.

Digitized by


Chemistry and Physics, 109

This it will be noticed is the composition of anthracite. In a subseqnent
letter to Les Mondes, M. le Gomte de Douhet, thus describes the mineral:
The nodules are globular, mammillated, consisting of concentric layers,
and occasionally possessiog a nearly perfect cleavage. Though fragile
and brittle, the fragments will scratch not only the hardest gems, but
also the diamond itself; though ordinary anthracite will not scratch
even glass. When facets are cut upon it, this singular mineral refracts
and disperses light with that white luster which is characteristic of the
diamond ; other and colored ^ms reflect light tinged with color ; while
the brilliance of the diamond is always white, even when it is itself col-
ored. Prismatic colors appear only when the light is refracted in the in-
terior of the crystal. This mineral, being opaque, cannot decompose
light, though it actively disperses it. These properties of hardness and
luster contrast strangely with the feeble density, anthracitic appearance,
and composition of uiis substance.

At the next session of the Academy, Dumas read a note from M^ne,
calling attention to some specimens of carbon presenting a similar ap-
pearance, which he had obtained artificially by heating in the muffle of
a cupel furnace for a long time the anthracite coal of Creuzot. It thus
acquires a metallic luster, steel-gray color, and scratches glass and steel
with the cry of the diamond. Its density is 1*637, and its composition
is carbon 96'8, volatile matter 1*0, ash 2*2=100. Mene also states that
the coke produced from a mixture of the Creuzot anthracite with the St.
Etienne bituminous, contains a multitude of brilliant points which read-
ily scratch glass-. — Comptes Bendus^ Ixiv, 54? and 674 ; Les Mondes, Apr.
11, 1867.

10. On the origin of meteorites, — In his researches on diffusion, Gra-
ham has shown that certain metals, such as iron, platinum, and gold,
which occur native in the soft colloid condition, readily absorb or occlude
gases. Hence by examination of the gases evolved from a meteorite for
example, the character of the atmosphere through which the ignited
mass has passed, may be determined. The well known Lenarto meteor-
ite is admirably adapted for such an experiment, beins very pure and
soft A piece 60 millimeters long, 13 wide and 10 thick, was cut from
the mass, cleansed and placed in a porcelain tube connected with a Spren-
gel aspirator. The tube was then heated in an ordinary combustion fur-
nace by ignited charcoal. Gas was freely evolved, which in 2^ hours
amounted to 16*53 cubic centimeters. This gas bhrned like hydrogen,
and when analyzed gave 85*68 hydrogen, 4*46 carbonic oxyd, 0*86 ni-
trogen in the 100. As the volume of the iron was 5*78 cc, it appears
to yield 2*85 times its volume of gas, of which 86 per cent is hydrogen.
Now, since hydrogen has been shown by spectrum analysis to be present
in the fixed stars, and by Secchi to be a principal element in some of
them, we may fairly suppose that the Lenarto meteorite has brought to
us the hydrogen of those distant bodies. Moreover it is found that mal-
leable iron can scarcely be made to occlude more than its own volume of
hydrogen under the ordinary atmospheric pressure. But the meteorite
gave uree times this quantity. Hence Graham infers that it must have
originated beyond the limits of the light cometary matter of 'our solar
system. — Chem. Hews, May 31, 1867.

Digitized by


1 1 Scientific Intelligence.

11. Action ofmangame peroxyd en uric add,^^. Gilbkbt Whekub
finds that when uric aoid is warmed with water and manganic peroxyd,
and sulphurio aoid added in small portions, so long as any action is ob-
served, the filtrate yields on concentration, crystals of parabanic add.
But that if the mixture of water and uric add be treated with the pei-
ozvd so long as carbonic dioxyd is evolved, and the whole filtered, man-
ganic oxalate is loft on the filter, and the filtrate contains allantoin and
urea. He gives the reaction as follows :

>J2+Mn€e3.— iWi the authot^e paper in the ZeiUdayi

fStr ChetMe.

12. Indium, — Fremy exhibited to the Academy on the 22Dd <3^ April,
in behalf of Professor Hichter who was present, two ingots of indium ob-
tained from the Freiberg blendes, which were about a dedmet^r high, and
a few centimeters in diameter, and weighed 500 grams. They were
valued at 20,000f.

18. Expaneion of metals and alloys by heat — ^A. MAiTmsaarar has ap-
plied the hydrostatic method — by means of which he determined the
expansion of water and mercury (see this Journal, IT, zliii, 254)— to
metals and alloys. The unit of volume at 0^ C. becomes at f C,

y 1 t ^ t \ <*

'"* ^10000 ^1000000 •

and is at 100^ C. equal to l-|-e. The values of a, h^ and o determined

by him are as follows :

a. 6. e.

Gadmiimi, 0*8078 0-140 00094*78

Zone, -8222 -070 89X8

Lead, *8177 -0222 8808

Tin, 6100 *0789 6889

SUver, '5488 H>405 5881

Copper, -4448 -0665 4998

Gold, -4075 -0886 4411

Bismuth, '8602 -0446 8948

PaUadium, '8082 *0280 8812

Antimony, -2770 -0897 8167

Platmmn, -2654 -0104 2658

He investigated the following 10 alloys: 1. Sn^Pb; 2. Pb^Sn; 8.
CdPb; 4. Sn^Zn; 5. SueZn; 6. Bi^^Sn; 1. BiSug; 8. Bi^^Pb; 9.
BiPb^; 10. Cu+(*8'85 vol.)Zn; 11. AuSn^; 12. Au^Sny; IS. Ag^
Au; 14. AgAu; 15. AgAu^ ; 16. AgH-(l 0-66 vol.) Pt; 17. On-f
(48'06 vol.) Au; 18. Gu-f(28'dl vol.) ^; 19. Cu4-(73-18 vol.) Ag.

The volume at 100^ C. was determined as above and also caleolated
from that of the component metals ; he obtained also the specific gravityt
and in an earlier investigation the electric conduetibility. The results
thus obtained are:

Na of Volame at 100* C. Bpeelflc gimTltT. CoodacUbaftr.

AUoj. ObMrveA. Oaleolatad. Obwnr. Cal& ObMnr. 0»lc

1. 1007188 1*007285 8*188 8-808 1057 10-68

2. 8419 8129 10690 10*646 8-28 848
8. 9188 8847 10-246 10-246 12*61 13-7t

4. 7184 7144 18-22 1846

5. 7058 7066 12-66 18'64

Digitized by


Chemistry and Physics. Ill

Ko.of Volnme at 100* C. Specific gnTity. Gonductibilitr.

AII07. ObMrred. Oaleolated. Observ. Calc ObMrv. Calc.

«. 4004 8978 9-808 9*801 0*245 1*28

1. 6098 6207 8772 8*788 8*96 6*59

8. 4086 4026 9*845 9*860 0*257 1*80

9. 8621 6007 10*956 10*541 209 4*28

10. 5719 6828 21*71 70*20

11. 4288 5919 11*888 11*978 14*27 85*51

18. 4423 6228 6*00 28*25

18. 5166 5649 12-257 IMli 20'»8 94*62

14. 4916 6128 14*870 14*847 14*59 86*62

15. 4800 4698 17*540 17*498 20*91 78*88

16. 4568 5207 6*70 88*60

17. 4657 4716 12*00 68*25

18. 5486 5288 67*85 95*00

19. 5718 5607 68*00 98*20

The volume at 0* G. being 1. From these tables Matthiewen con«
dudes that the volame (as well as the specifio gravity) of any alloy be-
tween 0^ and 100* C. nearly equals the mean of the volumes of the
sUoyed metals at the given temperature. In other words, neither vol-
une nor* specific gravity depends on the chemical nature of the alloy ;
while the fast two columns show that the electric oonductibility, not
being simply the calculated mean, does depend on the chemical condi-
tkm of the allov. In his concluding remarks, Matthieesen states that
he is able to calculate the conduotibiJity of any alloy if it be considered
as a '* aoUdified solution of one metal in the other.** — Pogg, AnnaUnj
1867, czxz, 50-76 ; Cosmos, 1867, v, 160. o. h.

14. Undvlatory theory qf hsat. — ^Babinkt says that his theory, first
pabiiahed in 1888 is still new ; we give the following extract from L'ln-
ititot, 1866, pp. 840-842.

Tks heat of a maUcule is its vis-viva ; two molecules are in caloric
etjuilibriam when they possess the same vis-viva. In this condition they
will, either at a distance or in contact exchange equal quantities of heat,
sod if placed in the same sphere, they will produce the same radiation.

If O represents the mass of a molecule of oxygen having a velocity v,
sad H and v', the same Quantities for hydrogen ; then these molecules
have the same quantity ot heat and the same temperature if

As 0=16H, we have v's4v.

For any two atoms m and m' with the velocities v and v' we have

At any other temperature these atoms are still in equilibrium if their
aew velocities of vibration u and u' fulfill

Consequently mv*—' mtt*=»»V*— mV*.

That is, the two atoms gain or lose the same quantities of heat between
two given temperatures. Or in other words, ths specific hsat cf element"
ary cUoms is eonsiantj which is the law of Dulong and Petit

According to Babine^ all molecules, vibrating separately, have the
tame vis-viva and heat, independent of the state of aggregation of the
body (solid, lii^uid or gaseous^. Hence the unit ofheat^or one dy-
namic calory — is the excess ot vis-viva of any molecule at 1^ C, above

Digitized by

Google —

112 Scientific Intelligence.

that which it has at 0® G. At this temperature, O*', the total quantity
of yis-viva of the molecule is very nearly 1 200 such units.

By combining two molecules so that they vibrate as one, Babinet
proves that their vis-viva will be doubled ; or if the final temperature is
to be the original temperature, the combination must lose a vis-viva equal
to that originally possessed by each of the molecules, or 1200 dynamic
calories (9).

The demonstration of the law of Dulong and Petit is favorable to the
peculiar views of Babinet ; but we must await further developments be-
fore we can form an intelligent opinion concerning the other parts of his
paper* o. h.

15. Action of heat on the optical properties of crystals, — ^DssCloi-
ZEAuz has determined optically the system of crystallization for quite a
number of minerals, hitherto imperfectly ascertamed, and has also made
some very important observations on the variation of the optical proper-
ties of crystals by heat. He finds :

(1.) On the optical properties of uniaxial crystals heat seems to have

Online LibraryJohn AlmonThe American journal of science and arts → online text (page 63 of 102)