Of the Combination of Acids with Salifiable Bases, and of the Formation
of Neutral Salts.
INTRODUCTION.
If I had strictly followed the plan I at first laid down for the conduct
of this work, I would have confined myself, in the Tables and
accompanying observations which compose this Second Part, to short
definitions of the several known acids, and abridged accounts of the
processes by which they are obtainable, with a mere nomenclature or
enumeration of the neutral salts which result from the combination of
these acids with the various salifiable bases. But I afterwards found
that the addition of similar Tables of all the simple substances which
enter into the composition of the acids and oxyds, together with the
various possible combinations of these elements, would add greatly to
the utility of this work, without being any great increase to its size.
These additions, which are all contained in the twelve first sections of
this Part, and the Tables annexed to these, form a kind of
recapitulation of the first fifteen Chapters of the First Part: The rest
of the Tables and Sections contain all the saline combinations.
It must be very apparent that, in this Part of the Work, I have borrowed
greatly from what has been already published by Mr de Morveau in the
First Volume of the _Encyclopedie par ordre des Matieres_. I could
hardly have discovered a better source of information, especially when
the difficulty of consulting books in foreign languages is considered. I
make this general acknowledgment on purpose to save the trouble of
references to Mr de Morveau's work in the course of the following part
of mine.
TABLE OF SIMPLE SUBSTANCES.
Simple substances belonging to all the kingdoms of nature, which may be
considered as the elements of bodies.
_New Names._ _Correspondent old Names._
Light Light.
Caloric {Heat.
{Principle or element of heat.
{Fire. Igneous fluid.
{Matter of fire and of heat.
Oxygen {Dephlogisticated air.
{Empyreal air.
{Vital air, or
{Base of vital air.
Azote {Phlogisticated air or gas.
{Mephitis, or its base.
Hydrogen {Inflammable air or gas,
{or the base of inflammable air.
Oxydable and Acidifiable simple Substance not Metallic.
_New Names._ _Correspondent old names._
Sulphur }
Phosphorous }The same names.
Charcoal }
Muriatic radical }
Fluoric radical }Still unknown.
Boracic radical }
Oxydable and Acidifiable simple Metallic Bodies
_New Names._ _Correspondent Old Names._
Antimony } { Antimony.
Arsenic } { Arsenic.
Bismuth } { Bismuth.
Cobalt } { Cobalt.
Copper } { Copper.
Gold } { Gold.
Iron } { Iron.
Lead } Regulus of { Lead.
Manganese } { Manganese.
Mercury } { Mercury.
Molybdena } { Molybdena.
Nickel } { Nickel.
Platina } { Platina.
Silver } { Silver.
Tin } { Tin.
Tungstein } { Tungstein.
Zinc } { Zinc.
Salifiable simple Earthy Substances.
_New Names._ _Correspondent old Names._
Lime {Chalk, calcareous earth.
{Quicklime.
Magnesia {Magnesia, base of Epsom salt.
{Calcined or caustic magnesia.
Barytes Barytes, or heavy earth.
Argill Clay, earth of alum.
Silex Siliceous or vitrifiable earth.
SECT. I.--_Observations upon the Table of Simple Substances._
The principle object of chemical experiments is to decompose natural
bodies, so as separately to examine the different substances which enter
into their composition. By consulting chemical systems, it will be found
that this science of chemical analysis has made rapid progress in our
own times. Formerly oil and salt were considered as elements of bodies,
whereas later observation and experiment have shown that all salts,
instead of being simple, are composed of an acid united to a base. The
bounds of analysis have been greatly enlarged by modern discoveries[36];
the acids are shown to be composed of oxygen, as an acidifying principle
common to all, united in each to a particular base. I have proved what
Mr Haffenfratz had before advanced, that these radicals of the acids
are not all simple elements, many of them being, like the oily
principle, composed of hydrogen and charcoal. Even the bases of neutral
salts have been proved by Mr Berthollet to be compounds, as he has shown
that ammoniac is composed of azote and hydrogen.
Thus, as chemistry advances towards perfection, by dividing and
subdividing, it is impossible to say where it is to end; and these
things we at present suppose simple may soon be found quite otherwise.
All we dare venture to affirm of any substance is, that it must be
considered as simple in the present state of our knowledge, and so far
as chemical analysis has hitherto been able to show. We may even presume
that the earths must soon cease to be considered as simple bodies; they
are the only bodies of the salifiable class which have no tendency to
unite with oxygen; and I am much inclined to believe that this proceeds
from their being already saturated with that element. If so, they will
fall to be considered as compounds consisting of simple substances,
perhaps metallic, oxydated to a certain degree. This is only hazarded as
a conjecture; and I trust the reader will take care not to confound what
I have related as truths, fixed on the firm basis of observation and
experiment, with mere hypothetical conjectures.
The fixed alkalies, potash, and soda, are omitted in the foregoing
Table, because they are evidently compound substances, though we are
ignorant as yet what are the elements they are composed of.
TABLE _of compound oxydable and acidifiable bases._
_Names of the radicals._
Oxydable or acidifiable { Nitro-muriatic radical or
base, from the mineral { base of the acid formerly
kingdom. { called aqua regia.
{ Tartarous radical or base.
{ Malic. }
{ Citric. }
{ Pyro-lignous. }
Oxydable or acidifiable { Pyro-mucous. }
hydro-carbonous or { Pyro-tartarous. }
carbono-hydrous radicals { Oxalic. }
from the vegetable { Acetous. }
kingdom. { Succinic. } Radicals
{ Benzoic. }
{ Camphoric. }
{ Gallic. }
}
Oxydable or acidifiable { Lactic. }
radicals from the animal { Saccholactic. }
kingdom, which { Formic. }
mostly contain azote, { Bombic. }
and frequently phosphorus. { Sebacic. }
{ Lithic. }
{ Prussic. }
_Note._--The radicals from the vegetable kingdom are converted by a
first degree of oxygenation into vegetable oxyds, such as sugar, starch,
and gum or mucus: Those of the animal kingdom by the same means form
animal oxyds, as lymph, &c.--A.
SECT. II.--_Observations upon the Table of Compound Radicals._
The older chemists being unacquainted with the composition of acids, and
not suspecting them to be formed by a peculiar radical or base for each,
united to an acidifying principle or element common to all, could not
consequently give any name to substances of which they had not the most
distant idea. We had therefore to invent a new nomenclature for this
subject, though we were at the same time sensible that this nomenclature
must be susceptible of great modification when the nature of the
compound radicals shall be better understood[37].
The compound oxydable and acidifiable radicals from the vegetable and
animal kingdoms, enumerated in the foregoing table, are not hitherto
reducible to systematic nomenclature, because their exact analysis is as
yet unknown. We only know in general, by some experiments of my own, and
some made by Mr Hassenfratz, that most of the vegetable acids, such as
the tartarous, oxalic, citric, malic, acetous, pyro-tartarous, and
pyromucous, have radicals composed of hydrogen and charcoal, combined
in such a way as to form single bases, and that these acids only differ
from each other by the proportions in which these two substances enter
into the composition of their bases, and by the degree of oxygenation
which these bases have received. We know farther, chiefly from the
experiments of Mr Berthollet, that the radicals from the animal kingdom,
and even some of those from vegetables, are of a more compound nature,
and, besides hydrogen and charcoal, that they often contain azote, and
sometimes phosphorus; but we are not hitherto possessed of sufficiently
accurate experiments for calculating the proportions of these several
substances. We are therefore forced, in the manner of the older
chemists, still to name these acids after the substances from which they
are procured. There can be little doubt that these names will be laid
aside when our knowledge of these substances becomes more accurate and
extensive; the terms _hydro-carbonous_, _hydro-carbonic_,
_carbono-hydrous_, and _carbono hydric_[38], will then become
substituted for those we now employ, which will then only remain as
testimonies of the imperfect state in which this part of chemistry was
transmitted to us by our predecessors.
It is evident that the oils, being composed of hydrogen and charcoal
combined, are true carbono-hydrous or hydro-carbonous radicals; and,
indeed, by adding oxygen, they are convertible into vegetable oxyds and
acids, according to their degrees of oxygenation. We cannot, however,
affirm that oils enter in their entire state into the composition of
vegetable oxyds and acids; it is possible that they previously lose a
part either of their hydrogen or charcoal, and that the remaining
ingredients no longer exist in the proportions necessary to constitute
oils. We still require farther experiments to elucidate these points.
Properly speaking, we are only acquainted with one compound radical from
the mineral kingdom, the nitro-muriatic, which is formed by the
combination of azote with the muriatic radical. The other compound
mineral acids have been much less attended to, from their producing less
striking phenomena.
SECT. III.--_Observations upon the Combinations of Light and Caloric
with different Substances._
I have not constructed any table of the combinations of light and
caloric with the various simple and compound substances, because our
conceptions of the nature of these combinations are not hitherto
sufficiently accurate. We know, in general, that all bodies in nature
are imbued, surrounded, and penetrated in every way with caloric, which
fills up every interval left between their particles; that, in certain
cases, caloric becomes fixed in bodies, so as to constitute a part even
of their solid substance, though it more frequently acts upon them with
a repulsive force, from which, or from its accumulation in bodies to a
greater or lesser degree, the transformation of solids into fluids, and
of fluids to aeriform elasticity, is entirely owing. We have employed
the generic name _gas_ to indicate this aeriform state of bodies
produced by a sufficient accumulation of caloric; so that, when we wish
to express the aeriform state of muriatic acid, carbonic acid, hydrogen,
water, alkohol, &c. we do it by adding the word _gas_ to their names;
thus muriatic acid gas, carbonic acid gas, hydrogen gas, aqueous gas,
alkoholic gas, &c.
The combinations of light, and its mode of acting upon different bodies,
is still less known. By the experiments of Mr Berthollet, it appears to
have great affinity with oxygen, is susceptible of combining with it,
and contributes alongst with caloric to change it into the state of gas.
Experiments upon vegetation give reason to believe that light combines
with certain parts of vegetables, and that the green of their leaves,
and the various colours of their flowers, is chiefly owing to this
combination. This much is certain, that plants which grow in darkness
are perfectly white, languid, and unhealthy, and that to make them
recover vigour, and to acquire their natural colours, the direct
influence of light is absolutely necessary. Somewhat similar takes place
even upon animals: Mankind degenerate to a certain degree when employed
in sedentary manufactures, or from living in crowded houses, or in the
narrow lanes of large cities; whereas they improve in their nature and
constitution in most of the country labours which are carried on in the
open air. Organization, sensation, spontaneous motion, and all the
operations of life, only exist at the surface of the earth, and in
places exposed to the influence of light. Without it nature itself would
be lifeless and inanimate. By means of light, the benevolence of the
Deity hath filled the surface of the earth with organization, sensation,
and intelligence. The fable of Promotheus might perhaps be considered as
giving a hint of this philosophical truth, which had even presented
itself to the knowledge of the ancients. I have intentionally avoided
any disquisitions relative to organized bodies in this work, for which
reason the phenomena of respiration, sanguification, and animal heat,
are not considered; but I hope, at some future time, to be able to
elucidate these curious subjects.
[Trancriber's note: The following table is presented in four sections to
comply with 75 character line limitation.]
TABLE of the binary Combinations of Oxygen with simple Substances
------------+----------------+-----------------------------------------+
|Names of |First degree of oxygenation. |
|the simple +--------------------+--------------------+
|substances. |New Names. |Ancient Names. |
+----------------+--------------------+--------------------+
{Caloric |Oxygen gas {Vital or |
{ | {dephlogisticated |
{ | {air |
{ | { |
{Hydrogen. |Water(A). | |
{ | | |
{Azote {Nitrous oxyd, or }Nitrous gas or air |
{ {base of nitrous gas } |
{ | | |
{Charcoal {Oxyd of charcoal, or}Unknown |
Combinations{ {carbonic oxyd } |
of oxygen { | | |
with {Sulphur |Oxyd of sulphur |Soft sulphur |
simple { | | |
non-metallic{Phosphorus |Oxyd of phosphorus {Residuum from the }
substances. { | {combustion of }
{ | {phosphorus }
{ | | |
{Muriatic radical}Muriatic oxyd |Unknown |
{ | | |
{Fluoric radical }Fluoric oxyd |Unknown |
{ | | |
{Boracic radical }Boracic oxyd |Unknown |
------------------------------------------------------------------------
{Antimony |Grey oxyd of |Grey calx of |
{ |antimony |antimony |
{ | | |
{Silver |Oxyd of silver |Calx of silver |
{ | | |
{Arsenic |Grey oxyd of arsenic|Grey calx of arsenic|
{ | | |
{Bismuth |Grey oxyd of bismuth|Grey calx of bismuth|
{ | | |
{ | | |
{Cobalt |Grey oxyd of cobalt |Grey calx of cobalt |
{ | | |
{Copper |Brown oxyd of copper|Brown calx of copper{
{ | | {
{Tin |Grey oxyd of tin |Grey calx of tin |
{ | | |
{Iron |Black oxyd of iron |Martial ethiops {
Combinations{ | | |
of oxygen {Manganese |Black oxyd of |Black calx of |
with the { |manganese |manganese |
simple { | | |
metallic {Mercury |Black oxyd of |Ethiops mineral(B) {
substances. { |mercury | {
{ | | |
{Molybdena |Oxyd of molybdena |Calx of molybdena |
{ | | |
{Nickel |Oxyd of nickel |Calx of nickel |
{ | | |
{Gold |Yellow oxyd of gold |Yellow calx of gold |
{ | | |
{Platina |Yellow oxyd of |Yellow calx of |
{ |platina |platina |
{ | | |
{Lead |Grey oxyd of lead |Grey calx of lead {
{ | | {
{Tungstein |Oxyd of Tungstein |Calx of Tungstein {
{ | | |
{Zinc |Grey oxyd of zinc |Grey calx of zinc |
------------+----------------+--------------------+--------------------+
------------+----------------+-----------------------------------------+
|Names of |Second degree of oxygenation. |
|the simple +--------------------+--------------------+
|substances. |New Names. |Ancient Names. |
+----------------+--------------------+--------------------+
{Caloric | | |
{ | | |
{Hydrogen. | | |
{ | | |
{Azote {Nitrous acid |Smoaking nitrous |
{ { |acid |
{ | | |
{Charcoal {Carbonous acid |Unknown |
Combinations{ { | |
of oxygen {Sulphur |Sulphurous acid |Sulphureous acid |
with simple { | | |
non-metallic{Phosphorus |Phosphorous acid {Volatile acid of }
substances. { | {phosphorus }
{ | | |
{Muriatic radical}Muriatous acid |Unknown |
{ | | |
{Fluoric radical }Fluorous acid |Unknown |
{ | | |
{Boracic radical }Boracous acid |Unknown |
------------------------------------------------------------------------
{Antimony |White oxyd of {White calx of }
{ |antimony {antimony }
{ | {diaphoretic antimony}
{ | | |
{Silver | | |
{ | | |
{Arsenic |White oxyd of |White calx of |
{ |arsenic |arsenic |
{ | | |
{Bismuth |White oxyd of |White calx of |
{ |bismuth |bismuth |
{ | | |
{Cobalt | | |
{ | | |
{Copper |Blue and green oxyds}Blue and green |
{ |of copper }calces of copper |
{ | | |
{Tin |White oxyd of tin {White calx of tin, }
{ | {or putty of tin }
{ | | |
{Iron |Yellow and red oxyds}Ochre and rust of |
{ |of iron }iron |
Combinations{ | | |
of oxygen {Manganese |White oxyd of |White calx of |
with the { |manganese |manganese |
simple { | | |
metallic {Mercury |Yellow and red oxyds{Turbith mineral, }
substances. { |of mercury {red precipitate, }
{ | {calcinated mercury, }
{ | {precipitate per se }
{ | | |
{Molybdena | | |
{ | | |
{Nickel | | |
{ | | |
{Gold |Red oxyd of gold {Red calx of gold, }
{ | {purple precipitate }
{ | |of cassius |
{ | | |
{Platina | | |
{ | | |
{Lead |Yellow and red oxyds}Massicot and minium |
{ |of lead } |
{ | | |
{Tungstein | | |
{ | | |
{Zinc |White oxyd of zinc {White calx of zinc, }
{ | {pompholix }
------------+----------------+--------------------+--------------------+
------------+----------------+-----------------------------------------+
|Names of |Third degree of oxygenation. |
|the simple +--------------------+--------------------+
|substances. |New Names. |Ancient Names. |
+----------------+--------------------+--------------------+
{Caloric | | |
{ | | |
{Hydrogen. | | |
{ | | |
{Azote {Nitric acid {Pale, or not }
{ { {smoaking nitrous }
{ | {acid |
{ | | |
Combinations{Charcoal {Carbonic acid |Fixed air |
of oxygen { | | |
with {Sulphur |Sulphuric acid |Vitriolic acid |
simple { | | |
non-metallic{Phosphorus |Phosphoric acid |Phosphoric acid |
substances. { | | |
{Muriatic radical}Muriatic acid |Marine acid |
{ | | |
{Fluoric radical }Fluoric acid |Unknown till lately |
{ | | |
{Boracic radical }Boracic acid {Homberg's sedative |
{ } {salt |
------------------------------------------------------------------------
{Antimony |Antimonic acid | |
{ | | |
{Silver |Argentic acid | |
{ | | |
{Arsenic |Arseniac acid |Acid of arsenic |
{ | | |
{Bismuth |Bismuthic acid | |
{ | | |
{Cobalt |Cobaltic acid | |
{ | | |
{Copper |Cupric acid | |
{ | | |
{Tin |Stannic acid | |
{ | | |
{Iron |Ferric acid | |
Combinations{ | | |
of oxygen {Manganese |Manganesic acid | |
with the { | | |
simple { | | |
metallic {Mercury |Mercuric acid | |
substances. { | | |
{Molybdena |Molybdic acid |Acid of molybdena {
{ | | |
{Nickel |Nickelic acid | |
{ | | |
{Gold |Auric acid | |
{ | | |
{Platina |Platinic acid | |
{ | | |
{Lead |Plumbic acid | |
{ | | |
{Tungstein |Tungstic acid |Acid of Tungstein {
{ | | |
{Zinc |Zincic acid | |
------------+----------------+--------------------+--------------------+
------------+----------------+------------------------------------------+
|Names of |Fourth degree of oxygenation. |
|the simple +---------------------+--------------------+
|substances. |New Names. |Ancient Names. |
+----------------+---------------------+--------------------+
{Caloric | | |
{ | | |
{Hydrogen. | | |
{ | | |
{Azote {Oxygenated nitric |Unknown |
{ {acid | |
{ | | |
{Charcoal {Oxygenated carbonic |Unknown |
Combinations{ {acid | |
of oxygen { | | |
with {Sulphur |Oxygenated sulphuric |Unknown |
simple { |acid | |
non-metallic{Phosphorus |Oxygenated phosphoric|Unknown |
substances. { |acid | |
{ | | |
{Muriatic radical}Oxygenated muriatic {Dephlogisticated |
{ |acid |marine acid |
{ | | |
{Fluoric radical } | |
{ | | |
{Boracic radical } | |
{ } | |
------------------------------------------------------------------------
{Antimony | | |
{ | | |
{Silver | | |
{ | | |
{Arsenic |Oxygenated arseniac |Unknown |
{ |acid | |
{ | | |
{Bismuth | | |
{ | | |
{Cobalt | | |
{ | | |
{Copper | | |
{ | | |
{Tin | | |
{ | | |
{Iron | | |
{ | | |
Combinations{ | | |
of oxygen {Manganese | | |
with the { | | |
simple { | | |
metallic {Mercury | | |
substances. { | | |
{Molybdena |Oxygenated molybdic |Unknown |
{ |acid | |
{Nickel | | |
{ | | |
{Gold | | |
{ | | |
{Platina | | |
{ | | |
{Lead | | |
{ | | |
{Tungstein |Oxygenated Tungstic }Unknown |
{ |acid | |
{ | | |
{Zinc | | |
------------+----------------+---------------------+--------------------+
[Note A: Only one degree of oxygenation of hydrogen is hitherto
known.--A.]
[Note B: Ethiops mineral is the sulphuret of mercury; this should have
been called black precipitate of mercury.--E.]
SECT. IV.--_Observations upon the Combinations of Oxygen with the simple
Substances._
Oxygen forms almost a third of the mass of our atmosphere, and is
consequently one of the most plentiful substances in nature. All the
animals and vegetables live and grow in this immense magazine of oxygen
gas, and from it we procure the greatest part of what we employ in
experiments. So great is the reciprocal affinity between this element
and other substances, that we cannot procure it disengaged from all
combination. In the atmosphere it is united with caloric, in the state
of oxygen gas, and this again is mixed with about two thirds of its
weight of azotic gas.
Several conditions are requisite to enable a body to become oxygenated,
or to permit oxygen to enter into combination with it. In the first
place, it is necessary that the particles of the body to be oxygenated
shall have less reciprocal attraction with each other than they have for
the oxygen, which otherwise cannot possibly combine with them. Nature,
in this case, may be assisted by art, as we have it in our power to
diminish the attraction of the particles of bodies almost at will by
heating them, or, in other words, by introducing caloric into the
interstices between their particles; and, as the attraction of these
particles for each other is diminished in the inverse ratio of their
distance, it is evident that there must be a certain point of distance
of particles when the affinity they possess with each other becomes less
than that they have for oxygen, and at which oxygenation must
necessarily take place if oxygen be present.
We can readily conceive that the degree of heat at which this phenomenon
begins must be different in different bodies. Hence, on purpose to
oxygenate most bodies, especially the greater part of the simple
substances, it is only necessary to expose them to the influence of the
air of the atmosphere in a convenient degree of temperature. With
respect to lead, mercury, and tin, this needs be but little higher than
the medium temperature of the earth; but it requires a more considerable
degree of heat to oxygenate iron, copper, &c. by the dry way, or when
this operation is not assisted by moisture. Sometimes oxygenation takes
place with great rapidity, and is accompanied by great sensible heat,
light, and flame; such is the combustion of phosphorus in atmospheric
air, and of iron in oxygen gas. That of sulphur is less rapid; and the
oxygenation of lead, tin, and most of the metals, takes place vastly
slower, and consequently the disengagement of caloric, and more
especially of light, is hardly sensible.
Some substances have so strong an affinity with oxygen, and combine with
it in such low degrees of temperature, that we cannot procure them in
their unoxygenated state; such is the muriatic acid, which has not
hitherto been decomposed by art, perhaps even not by nature, and which
consequently has only been found in the state of acid. It is probable
that many other substances of the mineral kingdom are necessarily
oxygenated in the common temperature of the atmosphere, and that being
already saturated with oxygen, prevents their farther action upon that
element.
There are other means of oxygenating simple substances besides exposure
to air in a certain degree of temperature, such as by placing them in
contact with metals combined with oxygen, and which have little affinity
with that element. The red oxyd of mercury is one of the best substances
for this purpose, especially with bodies which do not combine with that
metal. In this oxyd the oxygen is united with very little force to the
metal, and can be driven out by a degree of heat only sufficient to make
glass red hot; wherefore such bodies as are capable of uniting with
oxygen are readily oxygenated, by means of being mixed with red oxyd of
mercury, and moderately heated. The same effect may be, to a certain
degree, produced by means of the black oxyd of manganese, the red oxyd
of lead, the oxyds of silver, and by most of the metallic oxyds, if we
only take care to choose such as have less affinity with oxygen than the
bodies they are meant to oxygenate. All the metallic reductions and
revivifications belong to this class of operations, being nothing more
than oxygenations of charcoal, by means of the several metallic oxyds.
The charcoal combines with the oxygen and with caloric, and escapes in
form of carbonic acid gas, while the metal remains pure and revivified,
or deprived of the oxygen which before combined with it in the form of
oxyd.
All combustible substances may likewise be oxygenated by means of mixing
them with nitrat of potash or of soda, or with oxygenated muriat of
potash, and subjecting the mixture to a certain degree of heat; the
oxygen, in this case, quits the nitrat or the muriat, and combines with
the combustible body. This species of oxygenation requires to be
performed with extreme caution, and only with very small quantities;
because, as the oxygen enters into the composition of nitrats, and more
especially of oxygenated muriats, combined with almost as much caloric
as is necessary for converting it into oxygen gas, this immense quantity
of caloric becomes suddenly free the instant of the combination of the
oxygen with the combustible body, and produces such violent explosions
as are perfectly irresistible.
By the humid way we can oxygenate most combustible bodies, and convert
most of the oxyds of the three kingdoms of nature into acids. For this
purpose we chiefly employ the nitric acid, which has a very slight hold
of oxygen, and quits it readily to a great number of bodies by the
assistance of a gentle heat. The oxygenated muriatic acid may be used
for several operations of this kind, but not in them all.
I give the name of _binary_ to the combinations of oxygen with the
simple substances, because in these only two elements are combined. When
three substances are united in one combination I call it _ternary_, and
_quaternary_ when the combination consists of four substances united.
TABLE _of the combinations of Oxygen with the compound radicals._
_Names of the radicals._ _Names of the resulting acids._
_New nomenclature._ _Old nomenclature._
Nitro muriatic} Nitro muriatic acid Aqua regia.
radical }
(A)
Tartaric Tartarous acid Unknown till lately.
Malic Malic acid Ditto.
Citric Citric acid Acid of lemons.
Pyro-lignous Pyro-lignous acid Empyreumatic acid of wood.
Pyro-mucous Pyro-mucous acid Empyr. acid of sugar.
Pyro-tartarous Pyro-tartarous acid Empyr. acid of tartar.
Oxalic Oxalic acid Acid of sorel.
Acetic {Acetous acid Vinegar, or acid of vinegar.
{Acetic acid Radical vinegar.
Succinic Succinic acid Volatile salt of amber.
Benzoic Benzotic acid Flowers of benzoin.
Camphoric Camphoric acid Unknown till lately.
Gallic Gallic acid {The astringent principle
{of vegetables.
(B)
Lactic Lactic acid Acid of sour whey.
Saccholactic Saccholactic acid Unknown till lately.
Formic Formic acid Acid of ants.
Bombic Bombic acid Unknown till lately.
Sebacic Sebacic acid Ditto.
Lithic Lithic acid Urinary calculus.
Prussic Prussic acid Colouring matter of Prussian blue.
[Note A: These radicals by a first degree of oxygenation form vegetable
oxyds, as sugar, starch, mucus, &c.--A.]
[Note B: These radicals by a first degree of oxygenation form the animal
oxyds, as lymph, red part of the blood, animal secretions, &c.--A.]
SECT. V.--_Observations upon the Combinations of Oxygen with the
Compound Radicals._
I published a new theory of the nature and formation of acids in the
Memoirs of the Academy for 1776, p. 671. and 1778, p. 535. in which I
concluded, that the number of acids must be greatly larger than was till
then supposed. Since that time, a new field of inquiry has been opened
to chemists; and, instead of five or six acids which were then known,
near thirty new acids have been discovered, by which means the number of
known neutral salts have been increased in the same proportion. The
nature of the acidifiable bases, or radicals of the acids, and the
degrees of oxygenation they are susceptible of, still remain to be
inquired into. I have already shown, that almost all the oxydable and
acidifiable radicals from the mineral kingdom are simple, and that, on
the contrary, there hardly exists any radical in the vegetable, and more
especially in the animal kingdom, but is composed of at least two
substances, hydrogen and charcoal, and that azote and phosphorus are
frequently united to these, by which we have compound radicals of two,
three, and four bases or simple elements united.
From these observations, it appears that the vegetable and animal oxyds
and acids may differ from each other in three several ways: 1st,
According to the number of simple acidifiable elements of which their
radicals are composed: 2dly, According to the proportions in which these
are combined together: And, 3dly, According to their different degrees
of oxygenation: Which circumstances are more than sufficient to explain
the great variety which nature produces in these substances. It is not
at all surprising, after this, that most of the vegetable acids are
convertible into each other, nothing more being requisite than to change
the proportions of the hydrogen and charcoal in their composition, and
to oxygenate them in a greater or lesser degree. This has been done by
Mr Crell in some very ingenious experiments, which have been verified
and extended by Mr Hassenfratz. From these it appears, that charcoal and
hydrogen, by a first oxygenation, produce tartarous acid, oxalic acid by
a second degree, and acetous or acetic acid by a third, or higher
oxygenation; only, that charcoal seems to exist in a rather smaller
proportion in the acetous and acetic acids. The citric and malic acids
differ little from the preceding acids.
Ought we then to conclude that the oils are the radicals of the
vegetable and animal acids? I have already expressed my doubts upon
this subject: 1st, Although the oils appear to be formed of nothing but
hydrogen and charcoal, we do not know if these are in the precise
proportion necessary for constituting the radicals of the acids: 2dly,
Since oxygen enters into the composition of these acids equally with
hydrogen and charcoal, there is no more reason for supposing them to be
composed of oil rather than of water or of carbonic acid. It is true
that they contain the materials necessary for all these combinations,
but then these do not take place in the common temperature of the
atmosphere; all the three elements remain combined in a state of
equilibrium, which is readily destroyed by a temperature only a little
above that of boiling water[39].
TABLE _of the Binary Combinations of Azote with the Simple Substances._
_Simple Substances._ _Results of the Combinations._
_New Nomenclature._ _Old Nomenclature._
Caloric Azotic gas Phlogisticated air, or Mephitis.
Hydrogen Ammoniac Volatile alkali.
{Nitrous oxyd Base of Nitrous gas.
{Nitrous acid Smoaking nitrous acid.
Oxygen {Nitric acid Pale nitrous acid.
{Oxygenated nitric acid Unknown.
{This combination is hitherto unknown; should it
{ever be discovered, it will be called, according to
Charcoal {the principles of our nomenclature, Azuret of
{Charcoal. Charcoal dissolves in azotic gas, and
{forms carbonated azotic gas.
Phosphorus. Azuret of phosphorus. Still unknown.
{Azuret of sulphur. Still unknown. We know
Sulphur {that sulphur dissolves in azotic gas, forming
{sulphurated azotic gas.
{Azote combines with charcoal and hydrogen, and
Compound {sometimes with phosphorus, in the compound
radicals {oxydable and acidifiable bases, and is generally
{contained in the radicals of the animal acids.
{Such combinations are hitherto unknown; if ever
Metallic {discovered, they will form metallic azurets, as
substances {azuret of gold, of silver, &c.
Lime {
Magnesia {
Barytes {Entirely unknown. If ever discovered, they will
Argill {form azuret of lime, azuret of magnesia, &c.
Potash {
Soda {
SECT. VI.--_Observations upon the Combinations of Azote with the Simple
Substances._
Azote is one of the most abundant elements; combined with caloric it
forms azotic gas, or mephitis, which composes nearly two thirds of the
atmosphere. This element is always in the state of gas in the ordinary
pressure and temperature, and no degree of compression or of cold has
been hitherto capable of reducing it either to a solid or liquid form.
This is likewise one of the essential constituent elements of animal
bodies, in which it is combined with charcoal and hydrogen, and
sometimes with phosphorus; these are united together by a certain
portion of oxygen, by which they are formed into oxyds or acids
according to the degree of oxygenation. Hence the animal substances may
be varied, in the same way with vegetables, in three different manners:
1st, According to the number of elements which enter into the
composition of the base or radical: 2dly, According to the proportions
of these elements: 3dly, According to the degree of oxygenation.
When combined with oxygen, azote forms the nitrous and nitric oxyds and
acids; when with hydrogen, ammoniac is produced. Its combinations with
the other simple elements are very little known; to these we give the
name of Azurets, preserving the termination in _uret_ for all
nonoxygenated compounds. It is extremely probable that all the alkaline
substances may hereafter be found to belong to this genus of azurets.
The azotic gas may be procured from atmospheric air, by absorbing the
oxygen gas which is mixed with it by means of a solution of sulphuret of
potash, or sulphuret of lime. It requires twelve or fifteen days to
complete this process, during which time the surface in contact must be
frequently renewed by agitation, and by breaking the pellicle which
forms on the top of the solution. It may likewise be procured by
dissolving animal substances in dilute nitric acid very little heated.
In this operation, the azote is disengaged in form of gas, which we
receive under bell glasses filled with water in the pneumato-chemical
apparatus. We may procure this gas by deflagrating nitre with charcoal,
or any other combustible substance; when with charcoal, the azotic gas
is mixed with carbonic acid gas, which may be absorbed by a solution of
caustic alkali, or by lime water, after which the azotic gas remains
pure. We can procure it in a fourth manner from combinations of ammoniac
with metallic oxyds, as pointed out by Mr de Fourcroy: The hydrogen of
the ammoniac combines with the oxygen of the oxyd, and forms water,
whilst the azote being left free escapes in form of gas.
The combinations of azote were but lately discovered: Mr Cavendish first
observed it in nitrous gas and acid, and Mr Berthollet in ammoniac and
the prussic acid. As no evidence of its decomposition has hitherto
appeared, we are fully entitled to consider azote as a simple elementary
substance.
TABLE _of the Binary Combinations of Hydrogen with Simple Substances._
_Simple_ _Resulting Compounds._
_Substances._ _New Nomenclature._ _Old Names._
Caloric Hydrogen gas Inflammable air.
Azote Ammoniac Volatile Alkali.
Oxygen Water Water.
Sulphur {Hydruret of sulphur, or }
{sulphuret of hydrogen } Hitherto unknown (A).
Phosphorus {Hydruret of phosphorus, or }
{phosphuret of hydrogen }
Charcoal {Hydro-carbonous, or } Not known till lately.
{carbono-hydrous radicals(B)}
Metallic {Metallic hydrurets(C), as } Hitherto unknown.
substances, {hydruret of iron, &c. }
as iron, &c. { }
[Note A: These combinations take place in the state of gas, and form,
respectively, sulphurated and phosphorated oxygen gas--A.]
[Note B: This combination of hydrogen with charcoal includes the fixed
and volatile oils, and forms the radicals of a considerable part of the
vegetable and animal oxyds and acids. When it takes place in the state
of gas it forms carbonated hydrogen gas.--A.]
[Note C: None of these combinations are known, and it is probable that
they cannot exist, at least in the usual temperature of the atmosphere,
owing to the great affinity of hydrogen for caloric.--A.]
SECT. VII.--_Observations upon Hydrogen, and its Combinations with
Simple Substances._
Hydrogen, as its name expresses, is one of the constituent elements of
water, of which it forms fifteen hundredth parts by weight, combined
with eighty-five hundredth parts of oxygen. This substance, the
properties and even existence of which was unknown till lately, is very
plentifully distributed in nature, and acts a very considerable part in
the processes of the animal and vegetable kingdoms. As it possesses so
great affinity with caloric as only to exist in the state of gas, it is
consequently impossible to procure it in the concrete or liquid state,
independent of combination.
To procure hydrogen, or rather hydrogen gas, we have only to subject
water to the action of a substance with which oxygen has greater
affinity than it has to hydrogen; by this means the hydrogen is set
free, and, by uniting with caloric, assumes the form of hydrogen gas.
Red hot iron is usually employed for this purpose: The iron, during the
process, becomes oxydated, and is changed into a substance resembling
the iron ore from the island of Elba. In this state of oxyd it is much
less attractible by the magnet, and dissolves in acids without
effervescence.
Charcoal, in a red heat, has the same power of decomposing water, by
attracting the oxygen from its combination with hydrogen. In this
process carbonic acid gas is formed, and mixes with the hydrogen gas,
but is easily separated by means of water or alkalies, which absorb the
carbonic acid, and leave the hydrogen gas pure. We may likewise obtain
hydrogen gas by dissolving iron or zinc in dilute sulphuric acid. These
two metals decompose water very slowly, and with great difficulty, when
alone, but do it with great ease and rapidity when assisted by sulphuric
acid; the hydrogen unites with caloric during the process, and is
disengaged in form of hydrogen gas, while the oxygen of the water unites
with the metal in the form of oxyd, which is immediately dissolved in
the acid, forming a sulphat of iron or of zinc.
Some very distinguished chemists consider hydrogen as the _phlogiston_
of Stahl; and as that celebrated chemist admitted the existence of
phlogiston in sulphur, charcoal, metals, &c. they are of course obliged
to suppose that hydrogen exists in all these substances, though they
cannot prove their supposition; even if they could, it would not avail
much, since this disengagement of hydrogen is quite insufficient to
explain the phenomena of calcination and combustion. We must always
recur to the examination of this question, "Are the heat and light,
which are disengaged during the different species of combustion,
furnished by the burning body, or by the oxygen which combines in all
these operations?" And certainly the supposition of hydrogen being
disengaged throws no light whatever upon this question. Besides, it
belongs to those who make suppositions to prove them; and, doubtless, a
doctrine which without any supposition explains the phenomena as well,
and as naturally, as theirs does by supposition, has at least the
advantage of greater simplicity[40].
TABLE _of the Binary Combinations of Sulphur with Simple Substances._
_Simple_ _Resulting Compounds._
_Substances._ _New Nomenclature._ _Old Nomenclature._
Caloric Sulphuric gas
{ Oxyd of sulphur Soft sulphur.
Oxygen { Sulphurous acid Sulphureous acid.
{ Sulphuric acid Vitriolic acid.
Hydrogen Sulphuret of hydrogen }
Azote azote } Unknown Combinations.
Phosphorus phosphorus }
Charcoal charcoal }
Antimony antimony Crude antimony.
Silver silver
Arsenic arsenic Orpiment, realgar.
Bismuth bismuth
Cobalt cobalt
Copper copper Copper pyrites.
Tin tin
Iron iron Iron pyrites.
Manganese manganese
Mercury mercury Ethiops mineral, cinnabar.
Molybdena molybdena
Nickel nickel
Gold gold
Platina platina
Lead lead Galena.
Tungstein tungstein
Zinc zinc Blende.
{ Alkaline liver of sulphur
Potash potash { with fixed vegetable alkali.
{ Alkaline liver of sulphur
Soda soda { with fixed mineral
{ alkali.
{ Volatile liver of sulphur,
Ammoniac ammoniac { smoaking liquor
{ of Boyle.
Lime lime Calcareous liver of sulphur.
Magnesia magnesia Magnesian liver of sulphur.
Barytes barytes Barytic liver of sulphur.
Argill argill Yet unknown.
SECT. VIII.--_Observations on Sulphur, and its Combinations._
Sulphur is a combustible substance, having a very great tendency to
combination; it is naturally in a solid state in the ordinary
temperature, and requires a heat somewhat higher than boiling water to
make it liquify. Sulphur is formed by nature in a considerable degree of
purity in the neighbourhood of volcanos; we find it likewise, chiefly in
the state of sulphuric acid, combined with argill in aluminous schistus,
with lime in gypsum, &c. From these combinations it may be procured in
the state of sulphur, by carrying off its oxygen by means of charcoal in
a red heat; carbonic acid is formed, and escapes in the state of gas;
the sulphur remains combined with the clay, lime, &c. in the state of
sulphuret, which is decomposed by acids; the acid unites with the earth
into a neutral salt, and the sulphur is precipitated.
TABLE _of the Binary Combinations of Phosphorus with the Simple
Substances._
_Simple Substances._ _Resulting Compounds._
Caloric Phosphoric gas.
{ Oxyd of phosphorus.
Oxygen { Phosphorous acid.
{ Phosphoric acid.
Hydrogen Phosphuret of hydrogen.
Azote Phosphuret of azote.
Sulphur Phosphuret of Sulphur.
Charcoal Phosphuret of charcoal.
Metallic substances Phosphuret of metals(A).
Potash }
Soda }
Ammoniac } Phosphuret of Potash,
Lime } Soda, &c.(B)
Barytes }
Magnesia }
Argill }
[Note A: Of all these combinations of phosphorus with metals, that with
iron only is hitherto known, forming the substance formerly called
Siderite; neither is it yet ascertained whether, in this combination,
the phosphorus be oxygenated or not.--A.]
[Note B: These combinations of phosphorus with the alkalies and earths
are not yet known; and, from the experiments of Mr Gengembre, they
appear to be impossible--A.]
SECT. IX.--_Observations upon Phosphorus, and its Combinations._
Phosphorus is a simple combustible substance, which was unknown to
chemists till 1667, when it was discovered by Brandt, who kept the
process secret; soon after Kunkel found out Brandt's method of
preparation, and made it public. It has been ever since known by the
name of Kunkel's phosphorus. It was for a long time procured only from
urine; and, though Homberg gave an account of the process in the Memoirs
of the Academy for 1692, all the philosophers of Europe were supplied
with it from England. It was first made in France in 1737, before a
committee of the Academy at the Royal Garden. At present it is procured
in a more commodious and more oeconomical manner from animal bones,
which are real calcareous phosphats, according to the process of Messrs
Gahn, Scheele, Rouelle, &c. The bones of adult animals being calcined to
whiteness, are pounded, and passed through a fine silk sieve; pour upon
the fine powder a quantity of dilute sulphuric acid, less than is
sufficient for dissolving the whole. This acid unites with the
calcareous earth of the bones into a sulphat of lime, and the phosphoric
acid remains free in the liquor. The liquid is decanted off, and the
residuum washed with boiling water; this water which has been used to
wash out the adhering acid is joined with what was before decanted off,
and the whole is gradually evaporated; the dissolved sulphat of lime
cristallizes in form of silky threads, which are removed, and by
continuing the evaporation we procure the phosphoric acid under the
appearance of a white pellucid glass. When this is powdered, and mixed
with one third its weight of charcoal, we procure very pure phosphorus
by sublimation. The phosphoric acid, as procured by the above process,
is never so pure as that obtained by oxygenating pure phosphorus either
by combustion or by means of nitric acid; wherefore this latter should
always be employed in experiments of research.
Phosphorus is found in almost all animal substances, and in some plants
which give a kind of animal analysis. In all these it is usually
combined with charcoal, hydrogen, and azote, forming very compound
radicals, which are, for the most part, in the state of oxyds by a first
degree of union with oxygen. The discovery of Mr Hassenfratz, of
phosphorus being contained in charcoal, gives reason to suspect that it
is more common in the vegetable kingdom than has generally been
supposed: It is certain, that, by proper processes, it may be procured
from every individual of some of the families of plants.
As no experiment has hitherto given reason to suspect that phosphorus is
a compound body, I have arranged it with the simple or elementary
substances. It takes fire at the temperature of 32 deg. (104 deg.) of the
thermometer.
TABLE _of the Binary Combinations of Charcoal._
_Simple_
_Substances._ _Resulting Compounds._
{ Oxyd of charcoal Unknown.
Oxygen { Carbonic acid Fixed air, chalky acid.
Sulphur Carburet of sulphur }
Phosphorus Carburet of phosphorus } Unknown.
Azote Carburet of azote }
{ Carbono-hydrous radical
Hydrogen { Fixed and volatile oils
{ Of these only the carburets of
Metallic substances Carburets of metals { iron and zinc are known, and
{ were formerly called Plumbago.
Alkalies and earths Carburet of potash, &c. Unknown.
SECT. X.--_Observations upon Charcoal, and its Combinations with Simple
Substances._
As charcoal has not been hitherto decomposed, it must, in the present
state of our knowledge, be considered as a simple substance. By modern
experiments it appears to exist ready formed in vegetables; and I have
already remarked, that, in these, it is combined with hydrogen,
sometimes with azote and phosphorus, forming compound radicals, which
may be changed into oxyds or acids according to their degree of
oxygenation.
To obtain the charcoal contained in vegetable or animal substances, we
subject them to the action of fire, at first moderate, and afterwards
very strong, on purpose to drive off the last portions of water, which
adhere very obstinately to the charcoal. For chemical purposes, this is
usually done in retorts of stone-ware or porcellain, into which the
wood, or other matter, is introduced, and then placed in a reverberatory
furnace, raised gradually to its greatest heat: The heat volatilizes, or
changes into gas, all the parts of the body susceptible of combining
with caloric into that form, and the charcoal, being more fixed in its
nature, remains in the retort combined with a little earth and some
fixed salts.
In the business of charring wood, this is done by a less expensive
process. The wood is disposed in heaps, and covered with earth, so as to
prevent the access of any more air than is absolutely necessary for
supporting the fire, which is kept up till all the water and oil is
driven off, after which the fire is extinguished by shutting up all the
air-holes.
We may analyse charcoal either by combustion in air, or rather in oxygen
gas, or by means of nitric acid. In either case we convert it into
carbonic acid, and sometimes a little potash and some neutral salts
remain. This analysis has hitherto been but little attended to by
chemists; and we are not even certain if potash exists in charcoal
before combustion, or whether it be formed by means of some unknown
combination during that process.
SECT. XI.--_Observations upon the Muriatic, Fluoric, and Boracic
Radicals, and their Combinations._
As the combinations of these substances, either with each other, or with
the other combustible bodies, are hitherto entirely unknown, we have
not attempted to form any table for their nomenclature. We only know
that these radicals are susceptible of oxygenation, and of forming the
muriatic, fluoric, and boracic acids, and that in the acid state they
enter into a number of combinations, to be afterwards detailed.
Chemistry has hitherto been unable to disoxygenate any of them, so as to
produce them in a simple state. For this purpose, some substance must be
employed to which oxygen has a stronger affinity than to their radicals,
either by means of single affinity, or by double elective attraction.
All that is known relative to the origin of the radicals of these acids
will be mentioned in the sections set apart for considering their
combinations with the salifiable bases.
SECT. XII.--_Observations upon the Combinations of Metals with each
other._
Before closing our account of the simple or elementary substances, it
might be supposed necessary to give a table of alloys or combinations of
metals with each other; but, as such a table would be both exceedingly
voluminous and very unsatisfactory, without going into a series of
experiments not yet attempted, I have thought it adviseable to omit it
altogether. All that is necessary to be mentioned is, that these alloys
should be named according to the metal in largest proportion in the
mixture or combination; thus the term _alloy of gold and silver_, or
gold alloyed with silver, indicates that gold is the predominating
metal.
Metallic alloys, like all other combinations, have a point of
saturation. It would even appear, from the experiments of Mr de la
Briche, that they have two perfectly distinct degrees of saturation.
TABLE _of the Combinations of Azote in the state of Nitrous Acid with
the Salifiable Bases, arranged according to the affinities of these
Bases with the Acid_.
_Names of the bases._ _Names of the neutral salts._
_New nomenclature._ _Notes._
Barytes Nitrite of barytes. {
Potash potash. { These salts are only
Soda soda. { known of late, and
Lime lime. { have received no particular
Magnesia magnesia. { name in the old
Ammoniac ammoniac. { nomenclature.
Argill argill. {
{ As metals dissolve both in nitrous and
Oxyd of zinc zinc. { nitric acids, metallic salts must of
iron iron. { consequence be formed having
manganese manganese. { different degrees of oxygenation.
cobalt cobalt. { Those wherein the metal is
nickel nickel. { least oxygenated must be
lead lead. { called Nitrites, when more so,
tin tin. { Nitrats; but the limits of this
copper copper. { distinction are difficultly
bismuth bismuth. { ascertainable. The older
antimony antimony. { chemists were not acquainted
arsenic arsenic. { with any of these salts.
mercury mercury. {
silver { It is extremely probable that gold, silver
gold { and platina only form nitrats, and cannot subsist
platina { in the state of nitrites.
TABLE _of the Combinations of Azote, completely saturated with Oxygen,
in the state of Nitric Acid, with the Salifiable Bases, in the order of
the affinity with the Acid_.
_Bases._ _Names of the resulting neutral salts._
_New nomenclature._ _Old nomenclature._
Barytes Nitrat of barytes Nitre, with a base of heavy earth.
Potash potash Nitre, saltpetre. Nitre with base of potash.
Soda soda { Quadrangular nitre. Nitre with base of
{ mineral alkali.
{ Calcareous nitre. Nitre with
Lime lime { calcareous base. Mother water
{ of nitre, or saltpetre.
Magnesia magnesia Magnesian nitre. Nitre with base of magnesia.
Ammoniac ammoniac Ammoniacal nitre.
{ Nitrous alum. Argillaceous nitre. Nitre
Argill argill { with base of earth of alum.
Oxyd of zinc zinc Nitre of zinc.
iron iron Nitre of iron. Martial nitre. Nitrated iron.
manganese manganese Nitre of manganese.
cobalt cobalt Nitre of cobalt.
nickel nickel Nitre of nickel.
lead lead Saturnine nitre. Nitre of lead.
tin tin Nitre of tin.
copper copper Nitre of copper or of Venus.
bismuth bismuth Nitre of bismuth.
antimony antimony Nitre of antimony.
arsenic arsenic Arsenical nitre.
mercury mercury Mercurial nitre.
silver silver Nitre of silver or luna. Lunar caustic.
gold gold Nitre of gold.
platina platina Nitre of platina.
SECT. XIII.--_Observations upon the Nitrous and Nitric Acids, and their
Combinations._
The nitrous and nitric acids are procured from a neutral salt long known
in the arts under the name of _saltpetre_. This salt is extracted by
lixiviation from the rubbish of old buildings, from the earth of
cellars, stables, or barns, and in general of all inhabited places. In
these earths the nitric acid is usually combined with lime and magnesia,
sometimes with potash, and rarely with argill. As all these salts,
excepting the nitrat of potash, attract the moisture of the air, and
consequently would be difficultly preserved, advantage is taken, in the
manufactures of saltpetre and the royal refining house, of the greater
affinity of the nitric acid to potash than these other bases, by which
means the lime, magnesia, and argill, are precipitated, and all these
nitrats are reduced to the nitrat of potash or saltpetre[41].
The nitric acid is procured from this salt by distillation, from three
parts of pure saltpetre decomposed by one part of concentrated
sulphuric acid, in a retort with Woulfe's apparatus, (Pl. IV. fig. 1.)
having its bottles half filled with water, and all its joints carefully
luted. The nitrous acid passes over in form of red vapours surcharged
with nitrous gas, or, in other words, not saturated with oxygen. Part of
the acid condenses in the recipient in form of a dark orange red liquid,
while the rest combines with the water in the bottles. During the
distillation, a large quantity of oxygen gas escapes, owing to the
greater affinity of oxygen to caloric, in a high temperature, than to
nitrous acid, though in the usual temperature of the atmosphere this
affinity is reversed. It is from the disengagement of oxygen that the
nitric acid of the neutral salt is in this operation converted into
nitrous acid. It is brought back to the state of nitric acid by heating
over a gentle fire, which drives off the superabundant nitrous gas, and
leaves the nitric acid much diluted with water.
Nitric acid is procurable in a more concentrated state, and with much
less loss, by mixing very dry clay with saltpetre. This mixture is put
into an earthern retort, and distilled with a strong fire. The clay
combines with the potash, for which it has great affinity, and the
nitric acid passes over, slightly impregnated with nitrous gas. This is
easily disengaged by heating the acid gently in a retort, a small
quantity of nitrous gas passes over into the recipient, and very pure
concentrated nitric acid remains in the retort.
We have already seen that azote is the nitric radical. If to 20-1/2
parts, by weight, of azote 43-1/2 parts of oxygen be added, 64 parts of
nitrous gas are formed; and, if to this we join 36 additional parts of
oxygen, 100 parts of nitric acid result from the combination.
Intermediate quantities of oxygen between these two extremes of
oxygenation produce different species of nitrous acid, or, in other
words, nitric acid less or more impregnated with nitrous gas. I
ascertained the above proportions by means of decomposition; and, though
I cannot answer for their absolute accuracy, they cannot be far removed
from truth. Mr Cavendish, who first showed by synthetic experiments that
azote is the base of nitric acid, gives the proportions of azote a
little larger than I have done; but, as it is not improbable that he
produced the nitrous acid and not the nitric, that circumstance explains
in some degree the difference in the results of our experiments.
As, in all experiments of a philosophical nature, the utmost possible
degree of accuracy is required, we must procure the nitric acid for
experimental purposes, from nitre which has been previously purified
from all foreign matter. If, after distillation, any sulphuric acid is
suspected in the nitric acid, it is easily separated by dropping in a
little nitrat of barytes, so long as any precipitation takes place; the
sulphuric acid, from its greater affinity, attracts the barytes, and
forms with it an insoluble neutral salt, which falls to the bottom. It
may be purified in the same manner from muriatic acid, by dropping in a
little nitrat of silver so long as any precipitation of muriat of silver
is produced. When these two precipitations are finished, distill off
about seven-eighths of the acid by a gentle heat, and what comes over is
in the most perfect degree of purity.
The nitric acid is one of the most prone to combination, and is at the
same time very easily decomposed. Almost all the simple substances, with
the exception of gold, silver, and platina, rob it less or more of its
oxygen; some of them even decompose it altogether. It was very anciently
known, and its combinations have been more studied by chemists than
those of any other acid. These combinations were named _nitres_ by
Messrs Macquer and Beaume; but we have changed their names to nitrats
and nitrites, according as they are formed by nitric or by nitrous acid,
and have added the specific name of each particular base, to distinguish
the several combinations from each other.
TABLE _of the Combinations of Sulphuric Acid with the Salifiable Bases,
in the order of affinity._
_Names of the bases._ _Resulting compounds._
_New nomenclature._ _Old nomenclature._
Barytes Sulphat of barytes Heavy spar. Vitriol of heavy earth.
Potash potash {Vitriolated tartar. Sal
{ de duobus. Arcanum
{ duplicatam.
Soda soda Glauber's salt.
Lime lime Selenite, gypsum, calcareous vitriol.
Magnesia magnesia Epsom salt, sedlitz salt, magnesian vitriol.
Ammoniac ammoniac Glauber's secret sal ammoniac.
Argill argill Alum.
Oxyd of zinc zinc {White vitriol, goslar
{ vitriol, white coperas,
{ vitriol of zinc.
iron iron {Green coperas, green
{ vitriol, martial vitriol,
{ vitriol of iron.
manganese manganese Vitriol of manganese.
cobalt cobalt Vitriol of cobalt.
nickel nickel Vitriol of nickel.
lead lead Vitriol of lead.
tin tin Vitriol of tin.
copper copper {Blue coperas, blue vitriol,
{ Roman vitriol,
{ vitriol of copper.
bismuth bismuth Vitriol of bismuth.
antimony antimony Vitriol of antimony.
arsenic arsenic Vitriol of arsenic.
mercury mercury Vitriol of mercury.
silver silver Vitriol of silver.
gold gold Vitriol of gold.
platina platina Vitriol of platina.
SECT. XIV.--_Observations upon Sulphuric Acid and its Combinations._
For a long time this acid was procured by distillation from sulphat of
iron, in which sulphuric acid and oxyd of iron are combined, according
to the process described by Basil Valentine in the fifteenth century;
but, in modern times, it is procured more oeconomically by the
combustion of sulphur in proper vessels. Both to facilitate the
combustion, and to assist the oxygenation of the sulphur, a little
powdered saltpetre, nitrat of potash, is mixed with it; the nitre is
decomposed, and gives out its oxygen to the sulphur, which contributes
to its conversion into acid. Notwithstanding this addition, the sulphur
will only continue to burn in close vessels for a limited time; the
combination ceases, because the oxygen is exhausted, and the air of the
vessels reduced almost to pure azotic gas, and because the acid itself
remains long in the state of vapour, and hinders the progress of
combustion.
In the manufactories for making sulphuric acid in the large way, the
mixture of nitre and sulphur is burnt in large close built chambers
lined with lead, having a little water at the bottom for facilitating
the condensation of the vapours. Afterwards, by distillation in large
retorts with a gentle heat, the water passes over, slightly impregnated
with acid, and the sulphuric acid remains behind in a concentrated
state. It is then pellucid, without any flavour, and nearly double the
weight of an equal bulk of water. This process would be greatly
facilitated, and the combustion much prolonged, by introducing fresh air
into the chambers, by means of several pairs of bellows directed towards
the flame of the sulphur, and by allowing the nitrous gas to escape
through long serpentine canals, in contact with water, to absorb any
sulphuric or sulphurous acid gas it might contain.
By one experiment, Mr Berthollet found that 69 parts of sulphur in
combustion, united with 31 parts of oxygen, to form 100 parts of
sulphuric acid; and, by another experiment, made in a different manner,
he calculates that 100 parts of sulphuric acid consists of 72 parts
sulphur, combined with 28 parts of oxygen, all by weight.
This acid, in common with every other, can only dissolve metals when
they have been previously oxydated; but most of the metals are capable
of decomposing a part of the acid, so as to carry off a sufficient
quantity of oxygen, to render themselves soluble in the part of the acid
which remains undecomposed. This happens with silver, mercury, iron, and
zinc, in boiling concentrated sulphuric acid; they become first
oxydated by decomposing part of the acid, and then dissolve in the other
part; but they do not sufficiently disoxygenate the decomposed part of
the acid to reconvert it into sulphur; it is only reduced to the state
of sulphurous acid, which, being volatilised by the heat, flies off in
form of sulphurous acid gas.
Silver, mercury, and all the other metals except iron and zinc, are
insoluble in diluted sulphuric acid, because they have not sufficient
affinity with oxygen to draw it off from its combination either with the
sulphur, the sulphurous acid, or the hydrogen; but iron and zinc, being
assisted by the action of the acid, decompose the water, and become
oxydated at its expence, without the help of heat.
TABLE _of the Combinations of the Sulphurous Acid with the Salifiable
Bases, in the order of affinity._
_Names of the Bases._ _Names of the Neutral Salts._
Barytes Sulphite of barytes.
Potash potash.
Soda soda.
Lime lime.
Magnesia magnesia.
Ammoniac ammoniac.
Argill argill.
Oxyd of zinc zinc.
iron iron.
manganese manganese.
cobalt cobalt.
nickel nickel.
lead lead.
tin tin.
copper copper.
bismuth bismuth.
antimony antimony.
arsenic arsenic.
mercury mercury.
silver silver.
gold gold.
platina platina.
_Note._--The only one of these salts known to the old chemists was the
sulphite of potash, under the name of _Stahl's sulphureous salt_. So
that, before our new nomenclature, these compounds must have been named
_Stahl's sulphureous salt_, having base of fixed vegetable alkali, and
so of the rest.
In this Table we have followed Bergman's order of affinity of the
sulphuric acid, which is the same in regard to the earths and alkalies,
but it is not certain if the order be the same for the metallic
oxyds.--A.
SECT. XV.--_Observations upon Sulphurous Acid, and its Combinations._
The sulphurous acid is formed by the union of oxygen with sulphur by a
lesser degree of oxygenation than the sulphuric acid. It is procurable
either by burning sulphur slowly, or by distilling sulphuric acid from
silver, antimony, lead, mercury, or charcoal; by which operation a part
of the oxygen quits the acid, and unites to these oxydable bases, and
the acid passes over in the sulphurous state of oxygenation. This acid,
in the common pressure and temperature of the air, can only exist in
form of gas; but it appears, from the experiments of Mr Clouet, that, in
a very low temperature, it condenses, and becomes fluid. Water absorbs a
great deal more of this gas than of carbonic acid gas, but much less
than it does of muriatic acid gas.
That the metals cannot be dissolved in acids without being previously
oxydated, or by procuring oxygen, for that purpose, from the acids
during solution, is a general and well established fact, which I have
perhaps repeated too often. Hence, as sulphurous acid is already
deprived of great part of the oxygen necessary for forming the sulphuric
acid, it is more disposed to recover oxygen, than to furnish it to the
greatest part of the metals; and, for this reason, it cannot dissolve
them, unless previously oxydated by other means. From the same principle
it is that the metallic oxyds dissolve without effervescence, and with
great facility, in sulphurous acid. This acid, like the muriatic, has
even the property of dissolving metallic oxyds surcharged with oxygen,
and consequently insoluble in sulphuric acid, and in this way forms true
sulphats. Hence we might be led to conclude that there are no metallic
sulphites, were it not that the phenomena which accompany the solution
of iron, mercury, and some other metals, convince us that these metallic
substances are susceptible of two degrees of oxydation, during their
solution in acids. Hence the neutral salt in which the metal is least
oxydated must be named _sulphite_, and that in which it is fully
oxydated must be called _sulphat_. It is yet unknown whether this
distinction is applicable to any of the metallic sulphats, except those
of iron and mercury.
TABLE _of the Combinations of Phosphorous and Phosphoric Acids, with the
Salifiable Bases, in the Order of Affinity._
_Names of the_ _Names of the Neutral Salts formed by_
_Bases._ _Phosphorous Acid,_ _Phosphoric Acid._
Phosphites of(B) Phosphats of(C)
Lime lime lime.
Barytes barytes barytes.
Magnesia magnesia magnesia.
Potash potash potash.
Soda soda soda.
Ammoniac ammoniac ammoniac.
Argill argill argill.
Oxyds of(A)
zinc zinc zinc.
iron iron iron.
manganese manganese manganese.
cobalt cobalt cobalt.
nickel nickel nickel.
lead lead lead.
tin tin tin.
copper copper copper.
bismuth bismuth bismuth.
antimony antimony antimony.
arsenic arsenic arsenic.
mercury mercury mercury.
silver silver silver.
gold gold gold.
platina platina platina.
[Note A: The existence of metallic phosphites supposes that metals are
susceptible of solution in phosphoric acid at different degrees of
oxygenation, which is not yet ascertained.--A.]