Speaker 1: Section eighteen of the Science History of the Universe, Volume four.
Speaker 1: This is a LibriVox recording. All LibriVox recordings are in
Speaker 1: the public domain. For more information or to volunteer, please
Speaker 1: visit LibriVox dot org. The Science History of the Universe,
Speaker 1: Volume four, edited by Francis Rolt Wheeler. Chemistry, Chapter fourteen,
Speaker 1: Modern inorganic chemistry. Progress in inorganic chemistry during the modern period,
Speaker 1: a rapid growth in inorganic chemistry ensued after the introduction
Speaker 1: of the new chemistry by Levoisier. A massive information concerning
Speaker 1: the nature of the elements and their compounds was accumulated,
Speaker 1: and many new bodies were discovered. However, even now, after
Speaker 1: the accurate study of the chemical behavior of mineral substances
Speaker 1: by many careful investigators, we are still far from a
Speaker 1: definite knowledge of the nature of all the elements and
Speaker 1: their compounds, and new bodies are from time to time
Speaker 1: added to the extensive series already known. In the case
Speaker 1: of the elements, for example, Loisier in his Trey de
Speaker 1: Chemi mentioned twenty six while eighty one are at the
Speaker 1: present time accepted and endeavor to sketch. The important advantages
Speaker 1: in inorganic chemistry since the time of davy and gay
Speaker 1: lusac will be made in this chapter. Cadmium was discovered
Speaker 1: by Stromyer in eighteen seventeen and about the same time
Speaker 1: by Hermann. It was named by Stromeyer Cadmia fornicum or
Speaker 1: furnace zinc because it was found in the zinc furnace,
Speaker 1: Cadmia being the original name for zinc. In the same year,
Speaker 1: Lithium was discovered by Arvedsen in petolite in spotumine. The
Speaker 1: medal was first obtained by Bunsen and Matheson in eighteen
Speaker 1: fifty five. The name is Greek and means stony, and
Speaker 1: the metal was so called because it was then supposed
Speaker 1: to be found only in rocks and not in the
Speaker 1: plant in animal bodies. Silicon was first isolated in eighteen
Speaker 1: ten by Brasilius by fusing together iron, carbon and quartz,
Speaker 1: and Woolar showed that it exists in the chrystalline form
Speaker 1: as well as in the amorphous state. In eighteen twenty seven,
Speaker 1: Wooler isolated aluminum by the action of potassium upon its chloride,
Speaker 1: and eighteen years later Saint clair Deville prepared the metal
Speaker 1: on a large scale by using sodium while Bunsen effected
Speaker 1: its preparation by electrolytic means, aluminium is now prepared in
Speaker 1: quantity by the electrolytic decomposition of the oxide Alumina dissolved
Speaker 1: in cryolite. Beryllium or glucinum was also obtained by Wooler,
Speaker 1: who effected its isolation in eighteen twenty eight by the
Speaker 1: action of potassium upon the chloride. Bromine was isolated by
Speaker 1: Bollard in eighteen twenty six from the mother liquor of
Speaker 1: sea salt, and was further investigated three years later by Lowig.
Speaker 1: Along with iodine, which was discovered by Courtois in eighteen
Speaker 1: eleven in the ashes of sea plants and chlorine, it
Speaker 1: constituted the group of halogen elements of Berzelius, since fluorine
Speaker 1: was then unknown. The latter was first isolated in eighteen
Speaker 1: eighty six by Moi Sau by the electrolysis of hydrogen
Speaker 1: fluoride in the presence of potassium fluoride. Tellurium, which had
Speaker 1: been discovered by Mueller van Reckenstein in seventeen eighty two,
Speaker 1: was thoroughly investigated by Berzelius, who discovered an element chemically
Speaker 1: analogous to it selenium in eighteen seventeen. The isolation of
Speaker 1: the metals comprising the serrium and yttrium groups has presented
Speaker 1: numerous difficulties. Although the discovery of yttria, impure it is
Speaker 1: true from admixture with other earths, was accomplished by Godolin
Speaker 1: in seventeen ninety four, and investigators have busy themselves with
Speaker 1: the question. The chemistry of the serium metals is not
Speaker 1: even yet completely elucidated, and may possibly remain unsolved for
Speaker 1: considerable time to come. After claw Proth and Berselius had
Speaker 1: independently prepared serrium sesqua oxide from serite, and the latter
Speaker 1: had identified this as the oxide of a metal, Mozander
Speaker 1: discovered two new oxides in crude yttria, the metals of
Speaker 1: which lanthanum eighteen thirty four and didium eighteen forty one
Speaker 1: he isolated. Two years later, eighteen forty three, he added
Speaker 1: to these two others erbium and terbium, whose existence in
Speaker 1: nature is not yet, however definitely settled. In spite of
Speaker 1: the admirable work which has been done on the subject.
Speaker 1: This has given us a better knowledge of yttrium, while yttria,
Speaker 1: which was formerly held to be a homogeneous substance has
Speaker 1: proved itself a mixture of the oxides of various metals,
Speaker 1: of which, however, only one or two has yet been isolated,
Speaker 1: for example, the discovery of scandium by Nilsen and Cleeve
Speaker 1: in eighteen seventy nine and terbium by Mariak. The most
Speaker 1: recent additions to the knowledge of chemistry of this group
Speaker 1: of elements and their compounds have been made by Wellsbach, Drosbach, Cruz, Winkler, Crooks, Brauner, Baskerville, Urbane,
Speaker 1: and others. Wellsbock separated didium into praso and neoddium. An
Speaker 1: analytical method has been elaborated for the separation of the
Speaker 1: various constituents of serrium, terbium, and thorium earths, which has
Speaker 1: been of help in the manufacture of mantles for incandescent
Speaker 1: light burners. Quite recently, Urbane has separated etbium into two
Speaker 1: other elements, neo eterbium and lucium. In spectrum analysis, chemistry
Speaker 1: now possesses an exceedingly valuable instrument for investigating rare mentas
Speaker 1: and earths, and its use in the last five decades
Speaker 1: has been extensive. Spectrum analysis has grown out of some
Speaker 1: apparently insignificant and disconnected observations made by Margrov, Shiel, Herschel
Speaker 1: and others upon the light emitted by flames colored by
Speaker 1: certain salts. The spectra of such flames were investigated by
Speaker 1: various scientists, among whom Talbot, Miller, Altar, and Swann deserved
Speaker 1: first mentioned. But it was only after Kerkhoff in eighteen
Speaker 1: sixty proved the definite statement that every glowing vapor emits
Speaker 1: rays of the same degree of refrangibility that it absorbs
Speaker 1: that spectrum analysis became developed by Bunsen and himself into
Speaker 1: one of the great branches of our science. Its importance
Speaker 1: for analytical chemistry, especially in the discovery of new elements,
Speaker 1: is almost beyond mention, and it opened up a new
Speaker 1: era in chemistry. Roscoe once said, the spectroscope, next to
Speaker 1: the balance, is the most useful and important instrument which
Speaker 1: the chemist possesses. Crooks has remarked, if I name the
Speaker 1: spectroscope as the most important scientific invention of the latter
Speaker 1: half of this century, I shall not fear to be
Speaker 1: accused of exaggeration. The very importance of the subject prevents
Speaker 1: an entrance into any long discussion of it. Here it
Speaker 1: has come to form a distinct branch of chemical science.
Speaker 1: In the hands of men like Bunsen and Crooks. It
Speaker 1: has explored the recesses of the rocks for minute traces
Speaker 1: of hidden treasures, while with it workers like Miller, Huggins
Speaker 1: and Locheer have fathomed the abysses of space and determined
Speaker 1: the constitution of the stars. Among the elements discovered by
Speaker 1: the use of the spectroscope were rubidium and caesium in
Speaker 1: lepidolite and in the Durkheim mineral water by Bunsen and Kerkhoff,
Speaker 1: Indian by Reich and Richter in eighteen sixty three as
Speaker 1: a constituent of Freyburg, zinc, blend, gallium in eighteen seventy
Speaker 1: five by Les Coc des Bois bas Drawn, and thallium
Speaker 1: by Crooks in eighteen sixty one. The chemical nature of
Speaker 1: the last mentioned metal was established by Lamy in the
Speaker 1: same year. The knowledge of the metals discovered in the
Speaker 1: preceding era was greatly enlarged by investigations conducted during this period.
Speaker 1: The analogues of nitrogen, phosphorus, arsenic, antimony, and bismuth were
Speaker 1: carefully examined, and the atomic weight which Berselius determined for
Speaker 1: phosphorus was confirmed by Duma, while his atomic weight for
Speaker 1: arsenic was corroborated by Pelus and Duma. The metals of
Speaker 1: the alkaline earths barium, strontium, calcium, and magnesium, which were
Speaker 1: isolated by Davy, were investigated by Berselius, Mariac and Duma,
Speaker 1: who determined their atomic weights. Recently, Winkler found that magnesium
Speaker 1: is an excellent reducing agent for metallic oxides. Cobalt and
Speaker 1: n Nickel have been the subject of researches of an
Speaker 1: important nature, mainly because of the remarkable compounds they form,
Speaker 1: for example, nickel tetracarbonyl and the ammonio cobolic compounds. Nickel
Speaker 1: is now extensively used in metallurgy, especially in the production
Speaker 1: of nickel steel. The rarer metals have of course received
Speaker 1: considerable attention. Uranium, which was discovered by claw Proth in
Speaker 1: seventeen ninety eight, was investigated further by Pelago, Roscoe and
Speaker 1: lately by Zimmermann. Molybdenum and tungsten, isolated respectively by Helm
Speaker 1: and del Huriar have become better known, and the acids
Speaker 1: and the complicated salts of these have been studied by Scribbler, Mariac, Friedheim,
Speaker 1: and Gibbs. Uranium and particularly tungsten and molybdenum, are now
Speaker 1: employed extensively as steel hardening materials. Uranium compounds are also
Speaker 1: used in dyeing and ceramics. Titanium, zirconium, and thorium have
Speaker 1: now become in the form of various compounds, particularly the
Speaker 1: oxide of practical importance. Thorium was discovered by Berselius in
Speaker 1: eighteen twenty eight. Its oxide Thoria, is applied in the
Speaker 1: manufacture of Wellsbock gas mantles, which consists essentially of a
Speaker 1: web of ninety nine percent thoria and one percent serium oxide.
Speaker 1: Titanium is employed for the manufacture of special alloys, and
Speaker 1: zirconium Azirconia is made use of both in gas and
Speaker 1: electric illumination. Germanium, an element which resembles these in some respects,
Speaker 1: was discovered by Winkler in eighteen eighty six in a
Speaker 1: Freiberg silver ore. The element Vanandium, which was discovered by
Speaker 1: del Rio in eighteen oh one, was isolated by Roscoe
Speaker 1: in eighteen sixty seven. He also investigated its compounds, carefully
Speaker 1: determining its different stages of combination with oxygen and cline.
Speaker 1: This metal, which is widely distributed, is utilized in the
Speaker 1: production of sheet and toul steel and armor plates. Tantalum,
Speaker 1: a related metal, which along with columbium or neobium, was
Speaker 1: examined exhaustively by Blomstrand and Mariac, is used in alloys
Speaker 1: to make small springs and anvils, and in the metallic
Speaker 1: form to make special incandescent electric light filaments. The metals
Speaker 1: of the platinum group platinum, palladium wolston in eighteen O three,
Speaker 1: rhodium wolston in eighteen o four, iridium tenant in eighteen
Speaker 1: O three, osmium tenant in eighteen O three, and ruthenium
Speaker 1: klaus in eighteen forty four have been given careful consideration
Speaker 1: by chemists. Platinum is used extensively in making chemical apparatus,
Speaker 1: especially crucibles and stills, and osmium and iridium have recently
Speaker 1: come into use as filaments for incandescent lamps. About fifteen
Speaker 1: years ago, the number of the chemical elements was enlarged
Speaker 1: by two gases of great theoretical interest, argon and helium.
Speaker 1: As early as seventeen eighty five, Cavendish had noticed that
Speaker 1: a residue of about zero point six percent remained when
Speaker 1: the nitrogen and oxygen were removed from air, and in
Speaker 1: eighteen ninety four Raleigh discovered that nitrogen from the atmosphere
Speaker 1: was zero point five percent heavier than nitrogen prepared chemically.
Speaker 1: Raleigh and Ramsey then prepared large quantities of this atmospheric
Speaker 1: residue and found it to be a gas different from nitrogen.
Speaker 1: They called it argone, from the Greek argos for lazy.
Speaker 1: Helium was discovered by Ramsey in eighteen ninety five in
Speaker 1: the mineral clevite. It had already been found to exist
Speaker 1: in the chromosphere of the Sun by Jansen in eighteen
Speaker 1: sixty eight, and his observations were confirmed by Franklin and Lockier.
Speaker 1: Helium primarily obtained by heating clean with sulfuric acid, and
Speaker 1: since found in small quantity, often together with argon found
Speaker 1: in the mineral's uraniite, malacone, et cetera, as well as
Speaker 1: in the gases from some mineral water springs, is like argon,
Speaker 1: inert and indifferent. Up to now, in spite of persistent effort,
Speaker 1: no compound of either argone or helium has been prepared
Speaker 1: and Further, Although many diffusion experiments with both gases have
Speaker 1: been carried out with the object of seeing whether they
Speaker 1: were really elementary, the densities of both have remained unaltered.
Speaker 1: For example, it has been found impossible to subdivide them
Speaker 1: by diffusion into two or more components. From the ratio
Speaker 1: of the specific heats at constant volume and constant pressure,
Speaker 1: it follows that the molecule and atom are identical in
Speaker 1: both argon and helium, for example, that the gases are monatomic,
Speaker 1: and this applies also to the more recently discovered gases
Speaker 1: of the airton neon and xenon. These were separated from
Speaker 1: liquid air in eighteen ninety eight by Ramsey and Traverse.
Speaker 1: The atomic weights of these gases and the proportions in
Speaker 1: which they are present in the air are as follows.
Speaker 1: Helium atomic weight four one part by volume in air
Speaker 1: two thousand, four hundred and fifty volumes. Neon atomic weight
Speaker 1: twenty one part by volume in air, eight hundred eight volumes.
Speaker 1: Rgon atomic weight thirty nine point nine one part by
Speaker 1: volume in air, one hundred and five volumes. Krypton atomic
Speaker 1: weight eighty one point eight one part by volume in
Speaker 1: air seven hundred and forty six thousand volumes, xenon atomic
Speaker 1: weight one hundred and twenty eight one part by volume
Speaker 1: in air three million, eight hundred and forty six thousand volumes.
Speaker 1: Since the interest attached to these gases has been recently
Speaker 1: augmented by the discovery of Ramsey and Saudi that radium
Speaker 1: emanation eventually changes, at least in part into helium, and
Speaker 1: since Ramsey has shown that when the radium emanation decays
Speaker 1: in the presence of water, neon is produced, and that
Speaker 1: argone results when the decay takes place in the presence
Speaker 1: of water containing a copper salt in solution. The radioactive
Speaker 1: elements may be conveniently referred to here. Nribeckerrel found in
Speaker 1: eighteen ninety six that compounds of uranium spontaneously and continuously
Speaker 1: emit some radiation, which, among other properties, has that of
Speaker 1: making air a conductor of electricity. This effect, the quantity
Speaker 1: of which can be determined with great accuracy, was used
Speaker 1: by Madame Sklodowska Curie to measure the amount of radiation
Speaker 1: produced by various compounds of uranium and of thorium, which
Speaker 1: latter had been found by Schmidt to emit the same
Speaker 1: kind of radiation. She subsequently tested a large number of
Speaker 1: rocks and minerals and found that certain minerals which contain
Speaker 1: uranium and thorium, for example, pitchblend, oxide of uranium, calcolite,
Speaker 1: double phosphate of copper and uranium, possess radioactivity much greater
Speaker 1: than that theoretically due to the amount of uranium present.
Speaker 1: Madame Curie therefore inferred that it appeared probable that if pitchblend, calcolite,
Speaker 1: et cetera possessed so great a degree of activity, these
Speaker 1: substances contain a small quantity of a strongly radioactive body,
Speaker 1: differing from uranium and thorium and the simple bodies actually known.
Speaker 1: I thought that if this were indeed the case, I
Speaker 1: might hope to extract this substance from the ore by
Speaker 1: the ordinary methods of chemical analysis. The investigation was consequently pursued,
Speaker 1: and with the assistance of her husband, Pierre Curie and
Speaker 1: Gustav Beamont, Madame Curie commenced the la warious treatment of
Speaker 1: the residue remaining after the extraction of the uranium from pitchblend,
Speaker 1: a large quantity of which had been placed at her
Speaker 1: disposal by the Austrian government and finally separated the salts
Speaker 1: of radium in eighteen ninety eight. While endeavoring to isolate radium,
Speaker 1: Madame Curie discovered polonium, and other investigators De Bierney, Gazelle,
Speaker 1: mark Wald, and Hoffmann have given the names of actinium, imanium,
Speaker 1: radio tellurium, and radio led to similar substances, the two
Speaker 1: last being possible products of the spontaneous change in radium.
Speaker 1: Among those who have worked with success upon the problem
Speaker 1: of radioactivity, Elster and ghettl Rutherford, Saudi, and Ramsay may
Speaker 1: be mentioned here. Radium maintains a temperature one or more
Speaker 1: degrees above that of the atmosphere, injures the eyes and
Speaker 1: disorganizes the flesh when kept long in contact with it.
Speaker 1: Its peculiar properties have been explained in various ways. The
Speaker 1: most plausible suggestion is that atoms of high atomic weight
Speaker 1: slowly disintegrate into ultimate corpuscles or particles, and that this
Speaker 1: decomposition is attendant with the development of great energy. The
Speaker 1: successive disintegration of the radium atom, as exemplified by the
Speaker 1: disintegration of products, is shown in the following table, which
Speaker 1: represents according to Ernst Rutherford. The complete radium series as
Speaker 1: at present known. Radium radiation emitted alpha particles period two
Speaker 1: thousand years. Range of alpha particles in air at normal
Speaker 1: pressure three point five centimeters. Radium emanation radiation emitted alpha
Speaker 1: particles period thirty eight days. Range of alpha particles in
Speaker 1: air at normal pressure four point three centimeters. Radium A
Speaker 1: radiation emitted alpha particles period three minutes. Range of ALCA
Speaker 1: particles in air at normal pressure four point eight centimeters.
Speaker 1: Radium B radiation emitted beta particles period twenty six minutes.
Speaker 1: Radium C radiation emitted alpha and beta particles, gamma rays
Speaker 1: period nineteen minutes. Range of alpha particles in air at
Speaker 1: normal pressure seven point zero six centimeters. Radium D radiation
Speaker 1: emitted unknown period forty years. Radium E radiation emitted unknown
Speaker 1: period six days, Radium F radiation emitted beta particles period
Speaker 1: four point five days. Radium G radiation emitted alpha particles
Speaker 1: period one hundred and forty days. Range of alpha particles
Speaker 1: in air at normal pressure three point eight six centimeters.
Speaker 1: It appears that uranium is the source of radium, and
Speaker 1: Boltwood has recently announced the immediate parent of radium ionium.
Speaker 1: Radium represents barium chemically, and according to Madame Curi and Thorpe,
Speaker 1: it has an atomic weight of two hundred and twenty
Speaker 1: six point five. Several observers have demonstrated that it possesses
Speaker 1: a characteristic spectrum, and consequently, notwithstanding its disintegration and peculiar conduct,
Speaker 1: radium is regarded as a chemical element, owing to an
Speaker 1: affidation among chemists to recognize a body as a chemical
Speaker 1: element when under proper conditions it possesses a definite atomic
Speaker 1: weight and exhibits a spectrum containing characteristic and novel lines.
Speaker 1: In eighteen twenty three, Miskerlik discovered the existence of sulfur
Speaker 1: in two different chrystaline varieties, rhombic and oblique, and a
Speaker 1: third variety of plastic form was also known. Frankenheim learned
Speaker 1: that by heating and cooling, these varieties could, at definite temperatures,
Speaker 1: be converted into one another, and in describing these phenomena,
Speaker 1: the term isomerism was employed, to which, however, bersellia Is
Speaker 1: published an objection in eighteen forty one, to quote from
Speaker 1: his jahresbirict for that year, I feel compelled to call
Speaker 1: attention to the fact that the word isomerism, which is
Speaker 1: applied to different substances composed of an equal number of
Speaker 1: atoms of the same elements, is not compatible with the
Speaker 1: view as to the cause of the different properties exhibited
Speaker 1: by the various modifications of sulfur, carbon, silicon, et cetera.
Speaker 1: While the term still lends itself to the expression of
Speaker 1: the relation between ethyl formate and methylacetate, it is no
Speaker 1: longer suitable in the case of simple substances which assume
Speaker 1: different properties, and it might be desirable to substitute for
Speaker 1: a better chosen term, for example allotropy or allotropic modifications.
Speaker 1: In accordance with these views use there can be more
Speaker 1: than one cause for that which we call isomerism, namely
Speaker 1: one allotropy, in which case the difference between the sulfides
Speaker 1: of iron is due to the fact that they contain
Speaker 1: different modifications of sulfur. Two differences in the relative position
Speaker 1: of the atoms in the compound of which the two
Speaker 1: kinds of ether, ethyl formate and methyl lacetate are so
Speaker 1: striking a proof three a combination of one and two.
Speaker 1: Since then, the term allotropy has been in constant use,
Speaker 1: and numerous allotropic phenomena have been observed, particularly among the
Speaker 1: non metals. The allotropism of carbon was the first observed
Speaker 1: example seventeen seventy three, and its modifications exhibit marked points
Speaker 1: of difference. For instance, comparing diamond and graphite. Carbon diamond
Speaker 1: crystallographic system, cubic optical properties, colorless, transparent, high refractive index
Speaker 1: MEW equals two point four one seven, chemical and physical properties.
Speaker 1: Non conductor of heat and electricity not attacked by oxidizing agents.
Speaker 1: Ignition temperature seven hundred and sixty degrees to eight hundred
Speaker 1: and seventy five degrees, specific gravity three point five two
Speaker 1: hardness ten. Carbon graphite crystallographic system hexagonal or oblique optical properties, opaque,
Speaker 1: chemical and physical properties. Good conductor of heat and electricity
Speaker 1: oxidized to gryphytic acid. Ignition temperature five hundred and seventy
Speaker 1: five degrees and above, specific gravity two point twenty five
Speaker 1: hardness one. When amapherous carbon, coal, peat, lampblack, et cetera,
Speaker 1: and diamond are heated, they pass into the graphitic variety,
Speaker 1: and graphite is now produced in large amounts by heating
Speaker 1: carbon to a high temperature four thousand degrees celsius by
Speaker 1: an alternating electric current. En Remoisson eighteen fifty two to
Speaker 1: nineteen o seven, an eminent French chemist, succeeded in preparing
Speaker 1: synthetic diamonds by dissolving pure sugar charcoal in molten pure
Speaker 1: iron and suddenly cooling the mass by plunging it into water.
Speaker 1: And three English chemists, Sir F. A. Abel, W. H.
Speaker 1: Noble and Sir William Crooks, obtained diamonds by exploding some
Speaker 1: of the high explosives and steel bombs. The liquid carbon
Speaker 1: produced crystallizing as it cooled. However, no diamonds have thus
Speaker 1: far been produced of commercial size or amount. The most peculiar,
Speaker 1: as well as noteworthy example of allotropism is afforded by
Speaker 1: the conversion of oxygen into ozone. Ozone was first noticed
Speaker 1: by Van Marum in seventeen eighty five in electrified air.
Speaker 1: In eighteen forty, C. F. Schauenbein called attention again to
Speaker 1: this substance, discovering its oxidizing action, and showed that it
Speaker 1: was produced in the electrolysis of water and in the
Speaker 1: slow combustion of phosphorus and sulfur. He gave it the
Speaker 1: name ozone, which means a smell The investigations of Mariac
Speaker 1: des la Revee, Becquerel, Tait, Fremi, Andrews and Brodie have
Speaker 1: proved it to be modified oxygen. Its density was determined
Speaker 1: by Suret in eighteen sixty. The latter and before him,
Speaker 1: Andrews proved that the ozone molecule contains three atoms of oxygen,
Speaker 1: while a molecule of the latter is made up of
Speaker 1: two atoms. Ozone is now used in the sterilization of water.
Speaker 1: Among other allotropic modifications, those of selenium and phosphorus are
Speaker 1: of interest. Berzelius investigated the allotropes of selenium, and those
Speaker 1: of phosphorus were studied by Berselius, Stroder, Hittorf and schend
Speaker 1: Stroder discovered the red variety in anais eighteen forty five,
Speaker 1: and Hittor found that it could be transformed into a
Speaker 1: metallic modification. Several additional allotropes of sulfur have been discovered
Speaker 1: in late years, and the fact that many metals can
Speaker 1: exist in allotropic forms has been clearly demonstrated, for example,
Speaker 1: colloidal gold, silver, platinum, and mercury. The list of the
Speaker 1: compounds of the elements was greatly extended from the time
Speaker 1: of Laoissier. Particularly with the discovery of new acids and
Speaker 1: the growing knowledge of the different basity of the various acids,
Speaker 1: it is important to mention some of the discoveries of moment.
Speaker 1: In eighteen eighteen, one of the most interesting of inorganic
Speaker 1: compounds was discovered by Thienard. He proved that water is
Speaker 1: not the sole oxide of hydrogen, but that another peroxide
Speaker 1: of hydrogen, but which he termed oxygenated water, may be prepared.
Speaker 1: This compound plays a prominent role in many processes of nature,
Speaker 1: and is now prepared in quantities by treating barium dioxide
Speaker 1: with sulfuric acid for disinfecting and bleaching purposes. The list
Speaker 1: of the halogen acids was completed prior to eighteen twenty.
Speaker 1: Gay Lusac and Bollard study hydriotic and hydrobromic acids. The
Speaker 1: former Davi and Faraday investigated hydrochloric acid, while Thinard, gay Lusac,
Speaker 1: and Bresalius contributed greatly to an intimate knowledge of hydrofluoric acid.
Speaker 1: In eighteen sixty nine, Gore and Nicholas continued the investigation
Speaker 1: of anhydrous hydrofluoric acid, and the latter lost his life
Speaker 1: through its action, Gore and Fermi established its composition, but
Speaker 1: as before mentioned, the element fluorine was not isolated until
Speaker 1: eighteen eighty six. The oxygen compounds of chlorine, iodine, and
Speaker 1: bromine have been given much attention since the commencement of
Speaker 1: the nineteenth century. The work of gay Lusac on chloric acid,
Speaker 1: Ballard on hypochlorous acid, on chlorous acid, and Davy and
Speaker 1: Stadion on chlorine peroxide was exceedingly valuable and led to
Speaker 1: researches which firmly established the composition of these bodies. The
Speaker 1: oxygen compounds of iodine receive careful attention in the hands
Speaker 1: of Davy and Magnus, and the latter discovered iodic acid,
Speaker 1: the principal compound of that halogen. Following gay lusax discovery
Speaker 1: of hyposulfurrous acid in eighteen thirteen and dithionic acid in
Speaker 1: eighteen nineteen, little attention was given to the compounds of
Speaker 1: sulfur and oxygen until the fourth decade, when the thio acids,
Speaker 1: which contain more sulfur and are more closely related to
Speaker 1: sulfuric acid, were recognized. More recently, the early known oxides
Speaker 1: of sulfur, sulfur dioxide and sulfur trioxide have received several
Speaker 1: additions in sulfur cesqua oxide, sulfur tetroxide, and sulfur heptoxide.
Speaker 1: Sulfuric acid, the most important of all chemicals, is used
Speaker 1: in enormous quantities in the industries, and its manufacture has
Speaker 1: been immensely developed. Over two million tons were used in
Speaker 1: the United States in nineteen o eight. The very poisonous
Speaker 1: compounds of hydrogen with phosphorus, arsenic and antimony. Phosphine, arsine,
Speaker 1: and stibene were given considerable attention during the first and
Speaker 1: second decades of the modern period. Phosphine or hydrogen phosphid
Speaker 1: discovered in seventeen eighty three by Jenjibray, and its composition
Speaker 1: was studied by Davie Rose continued its investigation at a
Speaker 1: later date. Arceine was prepared in a pure state by
Speaker 1: Sue Bahrain Gellen fell a victim to its toxic action
Speaker 1: in eighteen fifteen. Phosphorus and phosphoric acids were known to Laoisier,
Speaker 1: but their constitution was not established until a much later period.
Speaker 1: It was upon the relations which gay, lusac, Stromyer and
Speaker 1: Graham found existing between the org tho pyro and metaphosphoric
Speaker 1: acids that Libig founded his theory of polybasic acids, which
Speaker 1: marks such an important step forward in chemistry. The important
Speaker 1: compound hydroxylamine, which may be regarded as ammonia in which
Speaker 1: a hydrogen atom has been replaced by hydroxyl h, was
Speaker 1: discovered by Lawsin in eighteen sixty five. It has led
Speaker 1: to a knowledge of many remarkable organic compounds. Similarly, the
Speaker 1: analogous compound hydrozene, which was first prepared by Curtis in
Speaker 1: eighteen eighty seven, has entered into the preparation of a
Speaker 1: series of interesting compounds, for example the hydrozoons and hydrozides.
Speaker 1: It is an exceedingly powerful reducing agent. Of the simple
Speaker 1: carbon compounds, the greater number were discovered in the first decade.
Speaker 1: Carbon disulfide, which was accidentally discovered by Lampadias in seventeen
Speaker 1: ninety six while heating pyrites with coal, was accurately examined
Speaker 1: by Voka in eighteen twelve. It is now prepared in
Speaker 1: an electric furnace by conducting sulfur vapor overheated carbon, and
Speaker 1: finds extensive use as a solvent. Carbonyl chloride or phosphene
Speaker 1: gas was discovered by Davy in eighteen eleven, and carbon
Speaker 1: oxysulfide by von Than quite recently. The compounds of carbon
Speaker 1: with certain metals carbides, are now of great technical importance.
Speaker 1: In eighteen o eight, Davy discovered potassium carbide, the first
Speaker 1: described in chemical literature, and in eighteen sixty two Wooler
Speaker 1: prepared calcium carbide, now one of the most important on
Speaker 1: account of its use in the generation of acetylene and
Speaker 1: in the manufacture of calcium cyanamide, a new constituent of fertilizers.
Speaker 1: Calcium carbide has since eighteen ninety four been prepared by
Speaker 1: fusing limestone and carbon together in an electric furnace. Before
Speaker 1: closing this brief resume of some of the advances made
Speaker 1: in the knowledge of chemical compounds mentioned must be made
Speaker 1: of the metallic peroxides, hydrides and nitrides. Sodium peroxide, which
Speaker 1: was discovered by gay Lusac, is now used extensively under
Speaker 1: the name oxone as a bleaching and oxidizing agent, and
Speaker 1: calcium peroxide, discovered by gay Lusac and Thinard, is used
Speaker 1: in dentistry. The discovery of the hydrides belongs to the
Speaker 1: present day. Among The most important of these is calcium
Speaker 1: hydride or hydrolyte, which is used for generating hydrogen. The
Speaker 1: metallic nitrides as magnesium, calcium, boron, and lithium nitrides have
Speaker 1: only lately been investigated carefully, but may become of great importance.
Speaker 1: Numerous important chemical and physical facts were learned concerning the
Speaker 1: gaseous bodies, especially during the second, third, and seventh decades,
Speaker 1: and the experiments which were conducted with a view of
Speaker 1: liquefying gases are of the highest import more particularly with
Speaker 1: regard to the production of liquid air and its application
Speaker 1: to researches at low temperatures. The experiments of Davy and Faraday,
Speaker 1: in which the gases were generated incurved closed glass tubes
Speaker 1: and cooled to about negative twenty degrees celsius in a
Speaker 1: freezing mixture, resulted in the liquefaction of all the common gases,
Speaker 1: with the exception of hydrogen, nitrogen, oxygen, methane, carbonic oxide,
Speaker 1: and nitric oxide. In eighteen thirty four, the Laurier liquefied
Speaker 1: carbon dioxide inconsiderable quantities and obtained the solid He was
Speaker 1: the first to operate on a large scale, and subsequent
Speaker 1: investigators made use of many of his observations. Between the
Speaker 1: years eighteen forty four and eighteen fifty five, Naturer studied
Speaker 1: the relationship of pressure and volume over wide ranges of pressure,
Speaker 1: and in eighteen fifty two he exposed hydrogen to a
Speaker 1: pressure of two thousand, seven hundred and ninety atmospheres, but
Speaker 1: was unable to effect its liquid faction. It was only
Speaker 1: in eighteen seventy seven that Raoul Pictae and Lewis kayla
Speaker 1: Tee succeeded almost simultaneously in liquefying the majority of the
Speaker 1: so called permanent gases. Their success was due to a
Speaker 1: recognition of the fact that reduction of temperature was necessary
Speaker 1: as well as pressure, but it was not possible by
Speaker 1: the aid of the methods and appliances which they employed
Speaker 1: to obtain the liquids in large quantities and to determine
Speaker 1: their physical constants. This was accomplished by Robluski, a chemist
Speaker 1: in Krakau, and he had Alzuski first obtained quantities of
Speaker 1: oxygen and nitrogen in the liquid state and describe many
Speaker 1: of their properties. These two investigators share with Twar and
Speaker 1: English chemist the honor of having first devised practical methods
Speaker 1: for the production of liquid air in quantity, and in
Speaker 1: eighteen ninety six see Linda in Germany and W. Hampson
Speaker 1: in England constructed technically efficient form of apparatus for producing
Speaker 1: liquid air. Liquid air has not as yet, however, found
Speaker 1: any technical application upon a large scale. Nearly pure oxygen
Speaker 1: is obtained from it very cheaply, and the attempt has
Speaker 1: been made to apply it in the manufacture of explosives.
Speaker 1: But so far liquid air has achieved the most important
Speaker 1: results in chemical research. In the first place, it must
Speaker 1: be mentioned that dear by its aid, has succeeded in
Speaker 1: liquefying hydrogen and in obtaining air, oxygen and hydrogen in
Speaker 1: the solid state, and that in doing so he has
Speaker 1: achieved almost everything that can be done in this direction. However,
Speaker 1: he is at present attempting to reach the so called
Speaker 1: absolute zero. The results that have been obtained by means
Speaker 1: of this agency with respect to the discovery of the
Speaker 1: noble gases are of greater importance. Since these have been described,
Speaker 1: it only remains to be stated that Ads, in his
Speaker 1: cryogenic laboratory in Leyden, has recently announced that he has
Speaker 1: liquefied helium and that it boils at negative two hundred
Speaker 1: and sixty eight point five degrees celsius. End of Section
Speaker 1: eighteen