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Friday, February 22, 2019

Antoine-Laurent de Lavoisier

Daniel Rutherford Jacobus Henricus Walther Hermann Nernst Reinh older Benesch & Ruth Erica Benesch Find How Oxygen is Transported in Human Body Frederick Soddy Artturi Ilmari Virtanen Louis Jacques Thenard receives kindle content peroxide Jbir ibn Hayyn Yaqub Al-Kindi Paul Karrer Antoine-Laurent de Lavoisier a few(prenominal) things argon as serious as irrigate, which we k instantly is set up of atomic emergence 8 and hydrogen. Did you know that Antoine Lavoisier was the discoverer of both elements? Contri exactlyions to Science Antoine-Laurent de Lavoisier is genius of the nigh(prenominal) in-chief(postnominal) scientists in the history of chemical teaching.He ascertained elements, realiseulated a basic equity of chemistry and helped create the careful formation. During his time, heap acceptd that when an intent burns, a opaque marrow cal take phlogiston was rel relieved. This was c solelyed the phlogiston conjecture. Lavoisiers experiments demonstrated t he contrary, i. e. when aroundwhatthing burned, it performanceu both(a)y absorbed something from the b na riding habitatedet, rather of releasing each(prenominal)thing. He afterward ca-cad the something from the nisus as atomic number 8, when he frame that it combine with other chemicals to form acid. (In disseverical, oxy mess historic period sharp, mendring to the sharp taste of acids. enthalpy Cavendish had earlier marooned hydrogen, only when he c whollyed it inflamm qualified air. Lavoisier ri check overd that this inflammable air burned to form a colour slight liquid, which turned out to be piddle. The Greek vocalise for water supply is hydro, so the air that burned to form water was hydrogen Lavoisier was kn bear for his painstaking attention to detail. Whenever he do a chemical reception, he weighed altogether the summations cargonfully before and after(prenominal) the reaction. He discovered that in a chemical reaction, though malls whitethorn change their chemical nature, their total mass t go acrossk the same.This is c e precise last(predicate)ed the law of saving of mass. His love for accuracy led to the formulation of the metric system of weights and measures which is c discharge up in use today. Lavoisiers attention to detail and riding habit of arrangement e trulything is perhaps his most important contri unlession for that is now the way knowledge is d angiotensin converting enzyme. Biography Lavoiser was innate(p) on 26 August 1743 in a wealthy Parisian family. He studied at the College Mazarin from 1754 to 1761. His interest in chemistry was developed as he read the wees of Etienne Condillac.In 1769, he set near making a geo lawful map of France, which was important for that countrys industrial development. In 1769, he took a brass position as a tax collector in the governing of King Louis xvi. In 1771, he married Marie-Anne Pierette Paulze, who is deemed as an eminent scientist in her own right. S he translated the run fors of m both scientists from English and German into French, and later on, with her husband, let on the Traite elementaire de chimie, often considered the low gear comprehensive book on the subject.In 1789, King Louis XVI was overthrown in the French Revolution. As Lavoisier had been a tax collector, he get the wrath of the revolutionaries, who executed him on 8 May 1794. SOURCE http//humantouchofchemistry. com/antoinelaurent-de-lavoisier. htm Elements and Atoms Ch apt(predicate)er 3 Lavoisiers Elements of Chemistry Antoine-Laurent Lavoisier (1743-1794) has been called the fo beneath of modern chemistry. (View a portrait of Mme. & M. Lavoisier by Jacque-Louis David at the Metropolitan Museum of Art, New York. Among his important contributions were the application of the balance and the dominion of conservation of mass to chemistry, the explanation of combustion and public discussion in foothold of conspiracy with oxygen rather than loss of phlogisto n (See chapter 5. ), and a reform of chemical linguistic communication. His Traite Elementaire de Chimie (1789), from which the conjure up extract is taken in a contemporary translation, was a enormously influential synthesis of his rifle. Lavoisier was a public servant as soundly as a scientist.Under the French monarchy, he was a member of the tax-collecting agency, the Ferme Generale. His work for the government include advocating rational agricultural methods and improving the manufacture of gunpowder. His operate to France continued during the Revolution. He was an alternate deputy of the reconvened E maintains-General in 1789, and from 1790 served on a commission charged with making weights and measures uniform across France. A Parisian by birth, Lavoisier also died in Paris, guillotined with other former members of the Ferme Generale during the Reign of curse in May 1794.The preface to his Traite Elementaire de Chimie is a fitting selection to celebrate Boyles The Sc eptical Chymist because it includes the definition of element that was to dominate chemistry doneout the adjacent century, and which is cool off familiar in our own day. In addition, Lavoisiers musings on the liaison between scholarship and the language which conveys its intellects tolerate thought-provoking, offseticularly in light-colored of the writings of Bertrand Russell, Ludwig Wittgenstein, and Alfred Ayer in the first half of the 20th century.Even his comments n premature the precept of introductory chemistry take sides in a debate that remains current. Antoine Lavoisier, Preface to Elements of Chemistry translation by Robert Kerr (Edinburgh, 1790), pp. xiii-xxxvii When I began the pursuit Work, my altogether object was to extend and explain to a greater conclusion fully the Memoir which I read at the public meeting of the Academy of Science in the month of April 1787, on the necessity of reforming and completing the linguistic surgical process of Chemistry1 .While engaged in this employment, I perceived, better than I had ever done before, the justice of the bonding mottos of the Abbe de Condillac2, in his System of Logic, and some other of his works. We say however through the medium of dustup. Languages ar accepted analytical methods. Algebra, which is adapted to its purpose in e rattling(prenominal) species of containion, in the most child same, most exact, and best look attainable, is at the same time a language and an analytical method. The art of argument is slide fastener to a greater extent than a language well arranged. Thus, mend I thought myself employed altogether in forming a speech, and spell I roposed to myself nonhing to a greater extent than to improve the chemical language, my work transformed itself by degrees, without my being able to pr eventidet it, into a treatise upon the Elements of Chemistry. The impossibility of separating the spoken language of a cognizance from the science itself, is o wing to this, that both branch of physical science must consist of three things the serial publication of facts which ar the objects of the science, the ideas which re puzzle these facts, and the words by which these ideas are expressed. Like three impressions of the same seal, the word ought to produce the idea, and the idea to be a picture of the fact.And, as ideas are keep and submitd by marrow of words, it necessarily follows that we nookie non improve the language of whatsoever science without at the same time improving the science itself n each ordure we, on the other hand, improve a science, without improving the language or nomenclature which belongs to it. However certain the facts of both science whitethorn be, and, withal just the ideas we may scoop up formed of these facts, we flock only communicate false impressions to others, darn we indigence words by which these may be goodly expressed. 3 To those who pass on consider it with attention, the first c ome a stir up of this treatise will reach frequent proofs of the truth of the above ceremonys. But as, in the conduct of my work, I strike been obliged to nonice an disparateiate of arrangement essentially differing from what has been adoptive in both other chemical work here(predicate)tofore publish, it is proper that I should explain the motives which fool led me to do so. It is a maxim universally admitted in geometry, and indeed in all(prenominal) branch of knowledge, that, in the progress of investigation, we should proceed from known facts to what is unknown quantity.In early infancy, our ideas spring from our indirect requests the sensation of want excites the idea of the object by which it is to be gratified. In this manner, from a series of sensations, observations, and analyses, a successive train of ideas arises, so linked together, that an attentive perceiver may trace back to a certain point the orderliness and connection of the whole sum of human knowle dge. When we begin the debate of any science, we are in a smudge, respecting that science, similar to that of children and the course by which we retain to advance is precisely the same which Nature follows in the formation of their ideas.In a child, the idea is merely an effect produced by a sensation and, in the same manner, in commencing the study of a physical science, we ought to form no idea but what is a necessary resolution, and immediate effect, of an experiment or observation. 4 Besides, he that enters upon the career of science, is in a less profitous situation than a child who is acquiring his first ideas. To the child, Nature de variances various agent of rectifying any mistakes he may commit respecting the salutary or foul qualities of the objects which surround him.On every occasion his judgments are corrected by screw want and pain are the necessary consequences arising from false judgment happiness and pleasure are produced by judging aright. Under such(p renominal) masters, we can non split to become well informed and we in short assume to causation justly, when want and pain are the necessary consequences of a contrary conduct. 5 In the study and practice of the sciences it is sort of incompatible the false judgments we form neither mask our experienceence nor our welfare and we are non forced by any physical necessity to correct them.Imagination, on the contrary, which is ever wandering beyond the bounds of truth, joined to self-love and that self-confidence we are so apt to indulge, prompt us to draw conclusions which are non immediately derived from facts so that we become in some measure interested in deceiving ourselves. then it is by no means to be wondered, that, in the science of natural philosophy in familiar, men pack often do suppositions, instead of forming conclusions.These suppositions, transfer down from one age to another, acquire additional weight from the government by which they are back up, til l at become they are received, even by men of genius, as perfect truths. The only method of preventing such errors from taking place, and of correcting them when formed, is to restrain and simplify our ratiocination as much as possible. This depends entirely upon ourselves, and the neglect of it is the only source of our mistakes. We must trust to nothing but facts These are nonpl utilise to us by Nature, and cannot deceive.We ought, in every instance, to submit our reasoning to the test of experiment, and never to search for truth but by the natural highway of experiment and observation. Thus mathematicians obtain the solution of a problem by the mere arrangement of data, and by reducing their reasoning to such artless stairs, to conclusions so very self-explanatory, as never to lose clutch of the evidence which guides them. 6 Thoroughly convinced of these truths, I induct compel upon myself, as a law, never to advance but from what is known to what is unknown never to fo rm any conclusion which is not an immediate consequence necessarily lowing from observation and experiment and always to arrange the fact, and the conclusions which are displace from them, in such an order as shall bed it most sluttish for beginners in the study of chemistry thoroughly to on a lower floorstand them. Hence I clear been obliged to depart from the usual order of courses of lectures and of treatises upon chemistry, which always assume the first principles of the science, as known, when the pupil or the reader should never be cogitated to know them till they have been explained in subsequent lessons.In about every instance, these begin by treating of the elements of look, and by explaining the table of affinities7, without considering, that, in so doing, they must bring the point phenomena of chemistry into diorama at the very outset They make use of terms which have not been defined, and suppose the science to be understood by the very persons they are only b eginning to teach. 8 It ought likewise to be considered, that very little of chemistry can be elateed in a first course, which is un tellly qualified to make the language of the science familiar to the ears, or the apparatus familiar to the eyes. It is around impossible to become a chemist in less than three or four historic period of constant application. These inconveniencies are occasioned not so much by the nature of the subject, as by the method of teaching it and, to avoid them, I was in the main induced to adopt a spic-and-span arrangement of chemistry, which appeared to me much consonant to the order of Nature.I acknowledge, however, that in gum olibanum endeavouring to avoid difficulties of one kind, I have found myself twisty in others of a different species, some of which I have not been able to remove but I am persuaded, that such as remain do not arise from the nature of the order I have adopted, but are rather consequences of the imperfection under which chem istry still labours.This science still has many an(prenominal) chasms, which interrupt the series of facts, and often render it extremely difficult to reconcile them with each other It has not, like the elements of geometry, the advantage of being a complete science, the parts of which are all nigh committed together Its actual progress, however, is so rapid, and the facts, under the modern doctrine, have assumed so happy an arrangement, that we have ground to hope, even in our own times, to see it approach near to the highest state of perfection of which it is susceptible. 9 The blotto law from which I have never deviated, of forming no conclusions which are not fully warranted by experiment, and of never make outing the absence of facts, has prevented me from comprehending in this work the branch of chemistry which treats of affinities, although it is perhaps the best calculated of any part of chemistry for being reduced into a completely dogmatic proboscis.Messrs Geoffroy, Gellert, Bergman, Scheele, De Morveau, Kirwan,10 and many others, have serene a number of accompaniment facts upon this subject, which only inhabit for a proper arrangement but the principal data are still wanting, or, at to the lowest degree, those we have are either not ablely defined, or not sufficiently proved, to become the foundation upon which to build so very important a branch of chemistry.This science of affinities, or elective attractions, holds the same place with regard to the other branches of chemistry, as the higher or transcendental geometry does with respect to the truthfulr and unsophisticated part and I thought it indelicate to involve those simple and plain elements, which I flatter myself the spectacularest part of my readers will easily understand, in the obscurities and difficulties which still attend that other very useful and necessary branch of chemical science. Perhaps a conceit of self-love may, without my perceiving it, have make believen add itional force to these reflections.Mr de Morveau is at present engaged in publishing the article Affinity in the organized Encyclopedia and I had more reasons than one to decline debut upon a work in which he is employed. It will, no doubt, be a theme of surprise, that in a treatise upon the elements of chemistry, there should be no chapter on the part and elementary parts of matter but I shall take occasion, in this place, to remark, that the fondness for reducing all the bodies in nature to three or four elements, proceeds from a prejudice which has descended to us from the Greek Philosophers.The conceit of four elements, which, by the variety of their symmetrys, compose all the known totals in nature, is a mere hypothesis, assumed long before the first principles of data-based philosophy or of chemistry had any existence. In those days, without possessing facts, they framed systems while we, who have collected facts, seem determined to reject them, when they do not agree w ith our prejudices.The authority of these fathers of human philosophy still carry great weight, and there is reason to fear that it will even bear hard upon generations save to come. 11 It is very remarkable, that, notwithstanding of the number of philosophical chemists who have supported the doctrine of the four elements, there is not one who has not been led by the evidence of facts to admit a greater number of elements into their theory.The first chemists that wrote after the revival of garners, considered sulphur and salinityiness as elementary substances entering into the composition of a great number of substances hence, instead of four, they admitted the existence of sextet elements. Beccher assumes the existence of three kinds of earth, from the combination of which, in different proportions, he sibyllic all the varieties of bi golden substances to be produced. Stahl gave a new modification to this system and succeeding chemists have taken the conversancy to make or t o imagine changes and additions of a similar nature. all(prenominal) these chemists were carried along by the influence of the genius of the age in which they lived, which cognitive subject areaed itself with assertions without proofs or, at least, often admitted as proofs the slightest degrees of probability, unsupported by that rigorously rigorous analysis required by modern philosophy. 12 All that can be said upon the number and nature of elements is, in my opinion, restrain to discussions entirely of a metaphysical nature. The subject only furnishes us with indistinct problems, which may be solved in a thousand different ways, not one of which, in all probability, is consistent with nature.I shall therefore only add upon this subject, that if, by the term elements, we mean to express those simple and inseparable atoms of which matter is composed, it is extremely probable we know nothing at all about them but, if we apply the term elements, or principles of bodies, to expr ess our idea of the last point which analysis is capable of reaching, we must admit, as elements, all the substances into which we are capable, by any means, to reduce bodies by decomposition. 13 Not that we are entitle to affirm, that these substances we consider as simple may not be deepen of 2, or even of a greater number of principles but, since these principles cannot be separated, or rather since we have not hitherto discovered the means of separating them, they act with regard to us as simple substances, and we ought never to suppose them deepen until experiment and observation has proved them to be so. 14 The foregoing reflections upon the progress of chemical ideas naturally apply to the words by which these ideas are to be expressed. direct by the work which, in the year 1787, Messrs de Morveau, Berthollet, de Fourcroy, and I composed upon the Nomenclature of Chemistry, I have endeavoured, as much as possible, to denominate simple bodies by simple terms, and I was nat urally led to reboot these first. 15 It will be recollected, that we were obliged to retain that expose of any substance by which it had been long known in the world, and that in twain bailiwicks only we took the liberty of making alterations first, in the case of those which were but newly discovered, and had not yet obtained label, or at least which had been known but for a bunco time, and the name calling of which had not yet received the sanction of the public and, secondly, when the names which had been adopted, whether by the ancients or the moderns, appeared to us to express evidently false ideas, when they bewildered the substances, to which they were utilise, with others possessed of different, or perhaps opposite qualities. We make no scruple, in this case, of substituting other names in their room, and the greatest number of these were borrowed from the Greek language. We endeavoured to frame them in such a manner as to express the most general and the most mark tonus of the substances and this was attended with the additional advantage both of assisting the memory of beginners, who find it difficult to remember a new word which has no meaning, and of accustoming them early to admit no word without connecting with it some determinate idea. 16 To those bodies which are formed by the union of several(prenominal) simple substances we gave new names, compounded in such a manner as the nature of the substances directed but, as the number of double combinations is already very considerable, the only method by which we could avoid confusion, was to divide them into classes. In the natural order of ideas, the name of the class or genus is that which expresses a quality common to a great number of individuals The name of the species, on the contrary, expresses a quality unusual to certain individuals only. 17 These distinctions are not, as some may imagine, merely metaphysical, but are established by Nature. A child, says the Abbe de Condillac, is taught to give the name tree to the first one which is pointed out to him. The next one he sees presents the same idea, and he gives it the same name. This he does likewise to a 3rd and a fourth, till at last the word tree, which he first applied to an individual, comes to be employed by him as the name of a class or a genus, an abstract idea, which comprehends all trees in general. But, when he learns that all trees serve not the same purpose, that they do not all produce the same kind of fruit, he will soon learn to give away them by specific and particular names. This is the logic of all the sciences, and is naturally applied of chemistry.The acids, for example, are compounded of two substances, of the order of those which we consider as simple the one constitutes acidity, and is common to all acids, and, from this substance, the name of the class or the genus ought to be taken the other is peculiar to each acid, and distinguishes it from the rest, and from this substance is to be taken the name of the species. But, in the greatest number of acids, the two constituent elements, the acidifying principle, and that which it acidifies, may exist in different proportions, constituting all the possible points of equilibrium or of saturation. This is the case in the sulphuric and the sulphurous acids and these two states of the same acid we have marked by varying the depot of the specific name. aluminiferous substances which have been exposed to the joint action of the air and of fire, lose their metallic lustre, increase in weight, and assume an earthy show.In this state, like the acids, they are compounded of a principle which is common to all, and one which is peculiar to each. In the same way, therefore, we have thought proper to class them under a generic name, derived from the common principle for which purpose, we adopted the term oxyd and we distinguish them from each other by the particular name of the metal to which each belongs. 18 Combustible su bstances, which in acids and metallic oxyds are a specific and particular principle, are capable of becoming, in their turn, common principles of a great number of substances. The sulphurous combinations have been long the only known ones in this kind.Now, however, we know, from the experiments of Messrs Vandermonde, Monge, and Berthollet, that fusain may be combine with iron, and perhaps with several other metals and that, from this combination, match to the proportions, may be produced steel, plumbago, &c. 19 We know likewise, from the experiments of M. Pelletier, that phosphorus may be combined with a great number of metallic substances. These different combinations we have classed under generic names taken from the common substance, with a termination which attach this analogy, specifying them by another name taken from that substance which is proper to each. The nomenclature of bodies compounded of three simple substances was attended with still greater difficulty, not only on direct of their number, but, peculiarly, because we cannot express the nature of their constituent principles without employing more compound names.In the bodies which form this class, such as the neutral salts, for instance, we had to consider, 1st, The acidifying principle, which is common to them all 2d, The acidifiable principle which constitutes their peculiar acid 3d, The saline, earthy, or metallic basis, which determines the particular species of salt. present we derived the name of each class of salts from the name of the acidifiable principle common to all the individuals of that class and sumptuous each species by the name of the saline, earthy, or metallic basis, which is peculiar to it. 20 A salt, though compounded of the same three principles, may, nevertheless, by the mere difference of their proportion, be in three different states.The nomenclature we have adopted would have been defective, had it not expressed these different states and this we win chiefly by changes of termination uniformly applied to the same state of the different salts. In short, we have advanced so far, that from the name all may be instantly found what the combustible substance is which enters into any combination whether that combustible substance be combined with the acidifying principle, and in what proportion what is the state of the acid with what basis it is united whether the saturation be exact, or whether the acid or the basis be in excess. It may be easily supposed that it was not possible to attain all these different objects without departing, in some instances, from established custom, and adopting terms which at first sight will appear uncouth and roughshod.But we considered that the ear is soon habituated to new words, curiously when they are connected with a general and rational system. The names, excessively, which were formerly employed, such as powder of algaroth, salt of alembroth, pompholix, phagadenic water, turbith mineral, colcothar, and many others, were neither less barbarous nor less uncommon. 21 It required a great take of practice, and no weakened degree of memory, to recollect the substances to which they were applied, much more to recollect the genus of combination to which they belonged. The names of oil of tartar per deliquium, oil of vitriol, butter of arsenic trioxide and of antimony, flowers of zinc, &c. ere still more improper, because they suggested false ideas For, in the whole mineral kingdom, and particularly in the metallic class, there exists no such thing as butters, oils, or flowers and, in short, the substances to which they give these fallacious names, are nothing less than rank poisons. 22 When we produce our essay on the nomenclature of chemistry, we were reproached for having changed the language which was spoken by our masters, which they idealistic by their authority, and handed down to us. But those who reproach us on this account, have forgotten that it was Bergman and Macquer themselves who urged us to make this reformation. In a letter which the learned Professor of Upsal, M. Bergman, wrote, a short time before he died, to M. de Morveau, he bids him spare no improper names those who are learned, will always be learned, and those who are ignorant will therefore learn sooner. 23 There is an objection to the work which I am going to present to the public, which is perhaps better founded, that I have addicted no account of the opinion of those who have gone before me that I have stated only my own opinion, without examining that of others. By this I have been prevented from doing that justice to my associates, and more especially to foreign chemists, which I tendered to render them. But I agitate the reader to consider, that, if I had filled an elementary work with a battalion of quotations if I had allowed myself to enter into long dissertations on the history of the science, and the works of those who have studied it, I must have lost sight of the tr ue object I had in view, and produced a work, the reading of which must have been extremely tiresome to beginners.It is not to the history of the science, or of the human mind, that we are to attend in an elementary treatise24 Our only aim ought to be ease and perspicuity, and with the utmost care to keep every thing out of view which might draw aside the attention of the student it is a road which we should be continually rendering more smooth, and from which we should endeavour to remove every obstacle which can occasion delay. The sciences, from their own nature, present a sufficient number of difficulties, though we add not those which are foreign to them. But, besides this, chemists will easily perceive, that, in the fist part of my work, I make very little use of any experiments but those which were made by myself If at any time I have adopted, without acknowledgment, the experiments or the opinions of M. Berthollet, M. Fourcroy, M. de la Place, M.Monge, or, in general, of any of those whose principles are the same with my own, it is owing to the circumstance, that frequent intercourse, and the habit of communicating our ideas, our observations, and our way of thinking to each other, has established between us a sort of community of opinions, in which it is often difficult for every one to know his own. 25 The remarks I have made on the order which I thought myself obliged to follow in the arrangement of proofs and ideas, are to be applied only to the first part of this work. It is the only one which contains the general sum of the doctrine I have adopted, and to which I wished to give a form completely elementary. 26 The second part is composed chiefly of tables of the nomenclature of the neutral salts. To these I have only added general explanations, the object of which was to point out the most simple processes for obtaining the different kinds of known acids. This part contains nothing which I can call my own, and presents only a very short abridgmen t of the results of these processes, extracted from the works of different authors. In the third part, I have inclined a description, in detail, of all the operations connected with modern chemistry. I have long thought that a work of this kind was much wanted, and I am convinced it will not be without use.The method of performing experiments, and particularly those of modern chemistry, is not so generally known as it ought to be and had I, in the different memoirs which I have presented to the Academy, been more particular in the detail of the manipulations of my experiments, it is probable I should have made myself better understood, and the science might have made a more rapid progress. The order of the different matters contained in this third part appeared to me to be almost arbitrary and the only one I have observed was to class together, in each of the chapters of which it is composed, those operations which are most connected with one another. I need hardly concern that th is part could not be borrowed from any other work, and that, in the principal articles it contains, I could not derive assistance from any thing but the experiments which I have made myself.I shall conclude this preface by transcribing, literally, some observations of the Abbe de Condillac, which I think describe, with a good deal of truth, the state of chemistry at a period not far distant from our own. These observations were made on a different subject but they will not, on this account, have less force, if the application of them be thought just. 27 Instead of applying observation to the things we wished to know, we have chosen rather to imagine them. Advancing from one ill founded supposition to another, we have at last bewildered ourselves amidst a deal of errors. These errors becoming prejudices, are, of course, adopted as principles, and we thus bewilder ourselves more and more. The method, too, by which we conduct our reasonings is as absurd we abuse words which we do not understand, and call this the art of reasoning.When matters have been brought this length, when errors have been thus accumulated, there is but one remedy by which order can be restored to the strength of thinking this is, to forget all that we have learned, to trace back our ideas to their source, to follow the train in which they rise, and, as my Lord Bacon says, to frame the human concord anew. This remedy becomes the more difficult in proportion as we think ourselves more learned. Might it not be thought that works which tempered of the sciences with the utmost perspicuity, with great precision and order, must be understood by every body? The fact is, those who have never studied any thing will understand them better than those who have studied a great deal, and especially those who have written a great deal. At the end of the fifth chapter, the Abbe de Condillac adds But, after all, the sciences have made progress, because philosophers have applied themselves with more attent ion to observe, and have communicated to their language that precision and accuracy which they have employed in their observations In correcting their language they reason better. Antoine Lavoisier, Table of impartial Substances in Elements of Chemistry translation by Robert Kerr (Edinburgh, 1790), pp. 175-6 Simple substances belonging to all the kingdoms of nature, which may be considered as the elements of bodies. New Names. Correspondent old Names. Light28 Light. thermic Heat. Principle or element of heat. Fire. Igneous fluid. Matter of fire and of heat. Oxygen29 Depholgisticated air. idealistic air. Vital air, or Base of vital air. Azote30 Phlogisticated air or heavy weapon. Mephitis, or its base. Hydrogen31 Inflammable air or gas, or the base of inflammable air. Oxydable32 and Acidifiable simple Substances not Metallic. New Names. Correspondent old names. Sulphur The same names. daystar Charcoal Muriatic radical33 Still unknown. Fluoric radical Boracic radical Oxydable and Acidifiable simple Metallic Bodies. New Names. Correspondent elder Names. Antimony Regulus34 of Antimony. Arsenic Arsenic bismuth Bismuth Cobalt Cobalt Copper Copper flamboyant Gold Iron Iron Lead Lead Manganese Manganese hectogram Mercury Molybdena35 Molybdena Nickel Nickel Platina Platina Silver Silver dismiss Tin Tungstein36 Tungstein Zinc Zinc Salifiable simple Earthy Substances37 New Names. Correspondent Old Names. Lime Chalk, calcareous earth. Quicklime. Magnesia Magnesia, base of Epsom salt. Calcined or caustic magnesia. barium sulfate Barytes, or heavy earth. Argill Clay, earth of alum. Silex Siliceous or vitrifiable earth. Notes 1Lavoisier read Methode de Nomenclature Chimique before the French Academy on 18 April 1787. This precis for a reformulation of chemical nomenclature was prepared by Lavoisier and three of his early converts to the oxygen theory of combustion, Louis Ber nard Guyton de Morveau, Claude Louis Berthollet, and Antoine Francois de Fourcroy. De Morveau had already argued for a reformed nomenclature, and he developed the April 1787 outline in a memoir read to the Academy on 2 May 1787. Leicester & Klickstein 1952 2Etienne Bonnot de Condillac (1715-1780) was a French philosopher and associate of Rousseau, Diderot, and the Encyclopedists.His La Logique (1780) stressed the richness of language as a tool in scientific and logical reasoning. 3Lavoisier makes an excellent point, but he overstates it. Clearly ones ideas are not strictly limited or determined by ones language. New ideas must exist before new terms can be coined to express those ideas thus new ideas can be formed and even to some extent described under the sway of older language. Also, new terms can only be defined by reference to pre-existing terms. sometimes new terms are not necessary, as old terms absorb new meanings. For example, I hope that the selections in this book show t o some extent how the terms atom and element have changed in meaning over time.Having made these points, I do not wish to minimize the ability of new terminology to help the mind to run along the path of new insights, or to prevent it from falling into old misconceptions. 4Note that Lavoisier does not say merely that we ought not believe any idea but what follows immediately and necessarily from experiment, we ought not even form the idea. This line shows a wariness of hypotheses common to many early scientists and natural philosophers. contrast Newtons, I frame no hypotheses for hypotheses have no place in experimental philosophy. in Bartlett 1980 Hypotheses had no part in the empirical methodology of Francis Bacon (1561-1626 see portrait at National Portrait Gallery, London), which emphasized aggregation and classification of facts. This aversion to hypotheses is too not urprising if one considers that empiricists were attempting to distance themselves from rationalism. su bsequent formulations of the scientific method, however, acknowledge the utility of hypotheses, always treated as provisional, in both suggesting experiments and interpreting them. 5Lavoisier was not the last to observe that children are born scientists who learn by experience. 6Lavoisiers choice of math as an example may strike a modern reader as odd. While mathematics has long served as an example of the kind of certainty to which scientists aspire ( numeral certainty), it is now seen as based on axioms, not through empirical observation based.Such mathematical systems as non-Euclidean geometry, which seemed to disagree with observed reality, had not yet been constructed at the time of Lavoisiers writing, though. 7A table of affinities was a summary of a great deal of data on chemical reactions. It lists what substances react chemically with a given substance, often in order of the vigor or extent of the reaction. (If substance A reacted more strongly than substance B with a giv en material, then substance A was said to have a greater affinity than B for that material. ) View a table of affinities by Etienne-Francois Geoffroy (1672-1731). 8In Lavoisiers mind, it makes no sense to jump to this summary table without first describing the various substances and their characteristic reactions.The proper role of descriptive chemistry in the chemical program continues to be a topic of debate in chemical education. patently Lavoisier would be quite sympathetic to the charge that introductory courses emphasize centripetal principles at the expense of descriptive chemistry. 9This is certainly an optimistic statement 2 hundred years later chemistry has developed to an extent Lavoisier could not have imagined, yet it is a rare and foolish chemist who expects the science to exhaust its possibilities for discovery within a lifetime. 10Bergman, Scheele, De Morveau, and Kirwan were all contemporaries of Lavoisier. The Swedish chemist Carl Wilhelm Scheele had a hand in t he discovery of oxygen, chlorine, and manganese.The Swedish chemist and mineralogist Torbern Bergman made contributions to analytical chemistry and the classification of minerals. Richard Kirwan was an Irish chemist and a defender of the phlogiston theory. 11The influence of the ancients was on the decline when Lavoisier wrote these words, but he does not exaggerate the importance of their thought. Remember that he is still concerned about their influence more than a century after The Sceptical Chymist and more than two millennia after the death of Aristotle. (See chapters 1 and 2. ) The simplicity of ancient ideas of matter would continue to have an influence on chemists well after Lavoisiers time, particularly as the number of chemical elements grew. (See chapter 10. 12Johann Joachim Becher (1635-1682) and Georg Ernst Stahl (1660-1734) were the two men most well associated with the phlogiston theory. Lavoisier was largely responsible for dislodging and discrediting the notion tha t combustion and respiration involved a loss of a subtle material called phlogiston. (See chapter 5. ) Lavoisier makes light of their ideas here, but the theory, though incorrect, was not as nonsensical as it may now appear. 13Notice the realness of Lavoisiers approach he suggests, in essence, forgetting about the ultimate building blocks of matter. This was a prudent recommendation, for he had no way of addressing that subject empirically (which is wherefore he dismisses it as metaphysical).He continues by suggesting that chemists turn their attention to what they can observe empirically, the ultimate products of chemical analysis. The definition of an element as a body which cannot be illogical down further by chemical analysis is an operational one as the techniques of chemical analysis improved, then substances scientists had any right to regard as elements could change. At first, this definition of element appears to be similar to that of Boyle. (See chapter 2, transmission line 9. ) However, Boyle seemed not to consider elementary substances which were not components of all compound matter. 14Lavoisiers table of simple bodies, reproduced below the preface, follows this prescription approximately, but not exactly. See note 33 below. ) 15See note 34 below on names of metals. 16Thus, where possible the name of a chemical substance should not simply be an arbitrary word, but should give some information about the substance. This principle is particularly evident in the modern systematic nomenclature of innate compounds the name enables one who knows the rules of nomenclature and some organic chemistry to draw the structural formula of a compound from its name. (See IUPAC 1979, 1993. ) The principle is also evident in the nomenclature of inorganic compounds IUPAC 1971, the class of compounds Lavoisiers nomenclature primarily addresses. It is least vident in modern names of the elements, many of which are named after important scientists (e. g. curium, me ndelevium, rutherfordium) or places important to the discoverers (e. g. polonium). (See Ringnes 1989 for etymology of elements names. ) Ironically, Lavoisier coined the name for an element key to his contributions to chemistry, a name of Greek origin chosen to convey information about the element which turned out to be incorrect. The name oxygen means acid former, for Lavoisier believed that oxygen was a component of all acids. 17Already we see the close connection Lavoisier envisioned between the language of chemistry and the content of the science.The system of naming compounds depends on classifying those compounds. Compounds belonging to the same class would have similar names. The name would also reflect the chemical composition of the substance. 18So the classes of compounds included acids, oxides, sulfides, and the like. To specify which acid, a particular name was added, e. g. nitrous acid. Different suffixes high-minded between similar particular names (such as sulfuric a nd blisteringthe -ic suffix applying to the more highly oxidize form). 19What Lavoisier has in mind is a class of materials now called carbides, inorganic compounds of a metal and carbon ( brown coal). But the examples he gives are not carbides.Steel is an alloy (a mixture or solution of metals, and therefore not a chemical compound of expressed proportions) in particular, steel is principally iron with some carbon and sometimes other metals (such as chromium or manganese). Although plumbago has been used to refer to a variety of lead-containing substances (as might be guessed from the root plumb-), it also (as here) refers to the substance now called graphite, the form of carbon commonly used for pencil leads. 20Again in the case of salts we see the nomenclature embodying the principles of the chemical theory of the day. A salt was seen as a compound of an acid and a base, and an acid itself a compound of an acidifiable part and an acidifying part.The acidifying part, whatever its nature, was believed to be common to all acids since it would not distinguish one salt from another, it does not appear in the name of the salt. The salts, then, carry the name of the acidifiable piece and the base with which it combines. 21Pompholix was a crude (i. e. , not very pure) zinc oxide (ZnO), sometimes known by the more loving but hardly more informative name flowers of zinc. Phagadenic water was a corrosive liquid used to cleanse ulcers phagadenic refers to a spreading or eating ulcer. Colcothar is a brownish-red mixture containing primarily ferric oxide (Fe2O3) with some calcium sulfate (CaSO4). Oxford 1971 22Oil of vitriol is sulfuric acid, a viscous liquid.Butter of arsenic (arsenic trichloride) is an oily liquid and butter of antimony (antimony trichloride) is a colorless deliquescent solid. In one sense, these names are informative, for they suggest the physical appearance of the substances they name they are, however, also misleading in the sense Lavoisier poi nts out. 23Lavoisier recognizes that even the most rationally designed nomenclature would be useless if chemists chose not to use it. A language is one of the most visible signs of a people and culture naturally, efforts to tamper with it can meet with disapproval. Thus Lavoisier pays at least nominal attention to aesthetic and cultural considerations, noting just above that the new terms sound no more barbarous than some practiced terms then in existence.In a similar vein, he makes a concession to linguistic conservatism still further above, where he indicates that he does not propose to displace familiar names, at least for elements. And here he concedes that one ought not lightly to tamper with language, but that in doing so he is responding to a need and a demand. 24Chemistry curricula in general devote little time to the history of the science, and that little usually consists of anecdotes broken among other material. Discoverers of laws and elements may be mentioned the path ways of discovery, however, let alone false steps on those pathways, almost never are. (See, however, Giunta 2001. In my opinion, the teaching of scientific process (as opposed to content) suffers as a result. The emphasis on current content to the exclusion of historical material, however, itself has a long history and such distinguished recommends as Lavoisier. 25The standards for crediting others for their ideas, particularly when they are similar to ones own, were not as crocked in Lavoisiers time as in our own. And yet Lavoisier was criticized even by contemporaries for failing to give what they believed to be sufficient credit. For instance, Joseph Priestley did not believe Lavoisier gave him sufficient credit for the discovery of dephlogisticated air (oxygen) when he described his own similar experiments Conant 1957.And Lavoisiers failure to credit James Watt and Henry Cavendish for their insights into the compound nature of water were a part of the sometimes rancorous wate r controversy Ihde 1964. See chapters 4 and 6 for articles on these subjects. 26The first part of the treatise deals with gases, caloric, and the combustion of elements, so it truly contains the work most closely associated with Lavoisier. 27Indeed, these words, which advocate empirical observation over rationalism as the source of authoritative knowledge, apply to any science. 28Light and caloric are not found on modern tables of elements because they are even matter, let alone elements of material bodies.Although a wave theory of light had been proposed by this time (by Christiaan Huygens), Newtons corpuscular (particle) theory was widely accepted until the 19th century. likewise, until the 19th century, heat was widely believed to be a material, a fluid which flowed out of hot bodies and into cold ones (even though mechanical theories of heat with a Newtonian pedigree also existed at this time). See chapter 5, note 17 for a description of Lavoisiers thinking about heat and fire . ) 29As mentioned above, the name oxygen means acid former, for Lavoisier believed (incorrectly) that oxygen was a component of all acids. Oxygen was a relatively recently discovered substance, and it did not have a standard name.The various names used for it are descriptive, but clumsy. Dephlogisticated air is particularly objectionable, for it described oxygen in terms of the phlogistion theory, which Lavoisier was in the process discrediting. 30The name azote and the current name due north were both used in English from the time of Lavoisier into the 19th century. Azote means lifeless, for breathing nitrogen does not sustain life. 31Hydrogen means water former, for water results from the burning of hydrogen. (See chapter 6. ) Hydrogen was one of several gases discovered in the eighteenth century. The names then in use for it were informative, denoting its flammability. 32I. e. substances which can be oxidized (combined with oxygen). 33These three radicals or roots had not yet b een isolated or properly characterized. The fluoric radical, now called fluorine, is the root of fluorspar and other fluorine-containing minerals. Fluorine is very difficult to separate from its compounds, and is a very reactive and dangerous gas in its elemental form. This gas was not isolated until 1886. The boracic radical, now called boron, is the root of the mineral borax (Na2B4O7) boron was not isolated until 1808. Weeks & Leicester, 1968 Muriatic acid was the name then in use for what we call hydrochloric acid or hydrogen chloride, HCl.Chlorine, the element which distinguishes this acid from others, was discovered by Carl Wilhelm Scheele however, he named it oxymuriatic acid, believing it to be a compound containing oxygen. Muriatic radical, then, was the name for the hypothetical element believed to be combined with oxygen in oxymuriatic acid. Muriatic, by the way, means pertaining to brine or salt Oxford 1971 the salt of muriatic acid is common table salt, atomic number 1 1 chloride (NaCl). Lavoisier had good reason to expect that these radicals would be isolated, for their compounds had been known for a long time however, the fluoric and boracic radicals were, strictly speaking, hypothetical substances at this time, and the basis of muriatic acid had already been isolated but he did not recognize it as elementary.Had he unploughed strictly to the principle of considering a substance an element if it could not be further decomposed, then Lavoisier should also have included oxymuriatic acid (undoubtedly by a different name) among the elements as it was, chlorine was named and recognized to be elementary only in 1810 Davy 1810, 1811. Although we can see, with hindsight, that Lavoisier was incorrect, it was by no means obvious at the time. Chlorine had been prepared from reactions with substances that do contain oxygen, for example from pyrolusite (MnO2) in Scheeles original isolation and from aqueous muriatic acid (HCl). 34Until the phlogiston theory was discarded, metals were commonly regarded as compounds of their minerals (earths) and phlogiston. This idea was incorrect, but it seemed to make sense, for the earths or ores seemed to be more fundamental than the metals.After all, the earths were found readily in nature, but to obtain the metals one had to heat the earths strongly in the presence of charcoal. In any event, the metal came to be known as the regulus of the mineral for example, the name antimony was before applied to an antimony sulfide, Sb2S3, and the metal was called regulus of antimony. Lavoisier drops the term regulus, giving the simple body (the metal) the simple, unmodified term. 35The element is now known as molybdenum. Similarly Lavoisiers platina is now called platinum. The ending is important the -um ending now denotes a metal, while the -a ending denotes an oxide of that metal. 36Now tungsten. 37All of these earthy substances proved to be compounds.Their elements were first isolated in the early 19th ce ntury. Of course, Lavoisier was justified in including them among his elements, for none of them had yet been broken down into anything simpler. Two interesting omissions from this table are soda and potash, comounds of sodium and potassium known since antiquity but whose elementary metals had not yet been extracted. One might have expected Lavoisier to list such substances either here or with the hypothesized radicals (note 33). Chalk frequently refered to calcium carbonate (CaCO3), but apparently it was also used for calcium oxide Oxford 1971. Magnesia is magnesium oxide, MgO. (See note 35. Epsom salt is magnesium sulfate, MgSO4, so named for the location (an English town) of a mineral spring from which the salt was obtained. Barytes is barium oxide, BaO. Argill or argil is an aluminum-containing potters clay. Alum is a transparent aluminum-containing mineral, AlK(SO4)2. 12H2O. Humphry Davy was the first to isolate calcium, magnesium, barium, Davy 1808b sodium, and potassium Davy 1808a he was also a co-discoverer of boron Davy 1809 and he recognized chlorine to be an element (note 34). Vitrifiable means able to be made into glass indeed, common glass is in the main silicon dioxide. Weeks & Leicester 1968 Source http//web. lemoyne. edu/giunta/ea/lavprefann. html Antoine-Laurent LavoisierAntoine-Laurent Lavoisier. Line engraving by Louis blue jean Desire Delaistre, after a design by Julien Leopold Boilly. courtesy blocking agent History of Medicine Collections, Moody Medical Library, University of Texas Medical Branch, Galveston, Texas. The son of a wealthy Parisian lawyer, Antoine-Laurent Lavoisier (17431794) completed a law degree in accordance with family wishes. His real interest, however, was in science, which he pursued with passion while leading a full public life. On the basis of his earliest scientific work, mostly in geology, he was elected in 1768at the early age of 25to the Academy of Sciences, Frances most selected scientific society.In the s ame year he bought into the Ferme Generale, the private corporation that collected taxes for the Crown on a profit-and-loss basis. A few years later he married the daughter of another tax farmer, Marie-Anne Pierrette Paulze, who was not quite 14 at the time. Madame Lavoisier prepared herself to be her husbands scientific collaborator by learning English to translate the work of British chemists like Joseph Priestley and by studying art and engraving to illustrate Antoine-Laurents scientific experiments. In 1775 Lavoisier was appointed a commissioner of the Royal Gunpowder and saltpeter Administration and took up residence in the Paris Arsenal.There he equip a fine laboratory, which attracted young chemists from all over Europe to learn about the Chemical Revolution then in progress. He slowdown succeeded in producing more and better gunpowder by increasing the supply and ensuring the purity of the constituentssaltpeter (potassium nitrate), sulfur, and charcoalas well as by improv ing the methods of granulating the powder. Characteristic of Lavoisiers chemistry was his systematic determination of the weights of reagents and products involved in chemical reactions, including the gaseous components, and his underlying belief that matter set by weightwould be conserved through any reaction (the law of conservation of mass).Among his contributions to chemistry associated with this method were the understanding of combustion and respiration as caused by chemical reactions with the part of the air (as discovered by Priestley) that he named oxygen, and his definitive proof by composition and decomposition that water is made up of oxygen and hydrogen. His giving new names to substancesmost of which are still used todaywas an important means of send on the Chemical Revolution, because these terms expressed the theory behind them. In the case of oxygen, from the Greek meaning acid-former, Lavoisier expressed his theory that oxygen was the acidifying principle. He cons idered 33 substances as elementsby his definition, substances that chemical analyses had failed to break down into simpler entities.Ironically, considering his opposition to phlogiston (see Priestley), among these substances was caloric, the unweighable substance of heat, and possibly light, that caused other substances to expand when it was added to them. To propagate his ideas, in 1789 he published a textbook, Traite Elementaire de chimie, and began a journal, Annales de Chimie, which carried research reports about the new chemistry almost exclusively. Antoine-Laurent Lavoisier conducts an experiment on human respiration in this drawing made by his wife, who depicted herself at the table on the far right. Courtesy Edgar Fahs Smith Memorial Collection, Department of Special Collections, University of Pennsylvania Library.A political and well-disposed liberal, Lavoisier took an active part in the events leading to the French Revolution, and in its early years he drew up plans and r eports advocating many reforms, including the establishment of the metric system of weights and measures. Despite his eminence and his services to science and France, he came under attack as a former farmer-general of taxes and was guillotined in 1794. A famed mathematician, Joseph-Louis Lagrange, remarked of this event, It took them only an instant to cut off that head, and a hundred years may not produce another like it. Source http//www. chemheritage. org/discover/online-resources/chemistry-in-history/themes/early-chemistry-and-gases/lavoisier. aspx Others http//preparatorychemistry. com/Bishop_nomenclature_help. htm

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