This website uses cookies to ensure you get the best experience. Learn more

atomic

atomic

atomic Sentence Examples

  • His book on Die modernen Theorien der Chemie, which was first published in Breslau in 1864, contains a discussion of relations between the atomic weights and the properties of the elements.

    164
    12
  • One remarkable discovery, however, of general interest, was the outcome of a long series of delicate weighings and minute experimental care in the determination of the relative density of nitrogen gas - undertaken in order to determine the atomic weight of nitrogen - namely, the discovery of argon, the first of a series of new substances, chemically inert, which occur, some only in excessively minute quantities, as constituents of the 1 The barony was created at George IV.'s coronation in 1821 for the wife of Joseph Holden Strutt, M.P. for Maldon (1790-1826) and Okehampton (1826-1830), who had done great service during the French War as colonel of the Essex militia.

    90
    5
  • The atomic weight of cadmium has been revised by G.

    78
    38
  • The atomic weight of cadmium has been revised by G.

    78
    38
  • By reducing the human mind to a series of unrelated atomic sensations, this teaching destroyed the possibility of knowledge, and further, by representing man as a "being who is simply the result of natural forces," it made conduct, or any theory of conduct, unmeaning; for life in any human, intelligible sense implies a personal self which (1) knows what to do, (2) has power to do it.

    31
    6
  • The atomic weight of the element has been determined by analysis.

    31
    11
  • The conclusion that each element had a definite atomic weight, peculiar to it, was the new idea that made his speculations fruitful, because it allowed of quantitative deduction and verification.

    30
    12
  • The atomic weight was determined by Cleve.

    26
    10
  • It is now agreed that the molecule of water contains two atoms of hydrogen and one of oxygen, so that the atomic weight of oxygen becomes 16, and similarly that the molecule of ammonia contains three atoms of hydrogen and one of nitrogen, and that consequently the atomic weight of nitrogen is 14.

    26
    12
  • The atomic weight of boron has been determined by estimating the water content of pure borax (J.

    21
    3
  • The above statement does not by any means exhaust the possible predictions that can be made from the atomic theory, but it shows how to test the theory.

    18
    5
  • Otherwise Berthollet's position would have been a much stronger one, and the atomic theory might have had to wait a long while for acceptance.

    18
    9
  • The atomic theory has been of priceless value to chemists, but it has more than once happened in the history of science that a hypothesis, after having been useful in the discovery Present and the co-ordination of knowledge, has been aban- position doned and replaced by one more in harmony with later of the discoveries.

    17
    5
  • The atomic weight of cadmium was found by 0.

    17
    10
  • The atomic weight of cadmium was found by 0.

    17
    10
  • That was indeed the hope for atomic energy in that era, and it did not pan out.

    15
    8
  • The atomic weight of ruthenium was determined by A.

    15
    9
  • The atomic weight of ruthenium was determined by A.

    15
    9
  • To "go nano" is to directly manipulate reality at the atomic level.

    14
    18
  • RUTHENIUM [[[symbol]] Ru, atomic weight To' 7 (O = 0)1, in chemistry, a metallic element, found associated with platinum, in platinum ore and in osmiridium.

    13
    8
  • The question is, however, vital to the atomic theory.

    13
    11
  • As the atomic weight of the element increases, it is found that the solubility of the sulphates in water decreases.

    11
    4
  • The neutralization of acids by bases affords many illustrations, known even before the atomic theory, of the truth of the statement.

    10
    4
  • In 1831, from a study of the specific heats of compounds, he formulated "Neumann's law," which expressed in modern language runs: "The molecular heat of a compound is equal to the sum of the atomic heats of its constituents."

    10
    4
  • Many varying values have been given for the atomic weight of molybdenum.

    10
    5
  • The atomic weight was determined by Berzelius, Erdmann and Marchand, Dumas and Stas.

    10
    5
  • Many varying values have been given for the atomic weight of molybdenum.

    10
    5
  • Apart from the atomic theory there is no obvious reason why this should be so.

    10
    7
  • If chemical compounds can be proved by experiment to obey these laws, then the atomic theory acquires a high degree of probability; if they are contradicted by experiment then the atomic theory must be abandoned, or very much modified.

    9
    4
  • On account of this difficulty, the atomic weights published by Dalton, and the more accurate ones of Berzelius, were not always identical with the values now accepted, but were often simple multiples or submultiples of these.

    9
    4
  • If chemical compounds can be proved by experiment to obey these laws, then the atomic theory acquires a high degree of probability; if they are contradicted by experiment then the atomic theory must be abandoned, or very much modified.

    9
    4
  • The discovery of this law is due to Dalton; it is a direct deduction from his atomic theory.

    9
    8
  • As Dalton said, "The doctrine of definite proportions appears mysterious unless we adopt the atomic hypothesis."

    8
    4
  • In water and in ethylene experiment shows that 8 parts by weight of oxygen and 6 parts of carbon, respectively, are in union with one part of hydrogen; also, if the diagrams are correct, these numbers must be in the ratio of the atomic weights of oxygen and carbon.

    6
    4
  • The above gives some idea of the evidence that has been accumulated in favour of the laws of chemical combination, laws which can be deduced from the atomic theory.

    6
    9
  • In fact, he did so much to make the atomic theory of matter probable that he is popularly regarded as its originator.

    3
    4
  • BORON (symbol B, atomic weight ii), one of the non-metallic elements, occurring in nature in the form of boracic (boric) acid, and in various borates such as borax, tincal,.

    0
    0
  • YTTRIUM [[[symbol]], Y; atomic weight, 89 o (0= 16)], a metallic chemical element.

    0
    0
  • CADMIUM (symbol Cd, atomic weight I12.4 (0=16)), a metallic element, showing a close relationship to zinc, with which it is very frequently associated.

    0
    0
  • MOLYBDENUM [[[symbol]], Mo; atomic weight, 96 (0=16)] a metallic chemical element.

    0
    0
  • GERMANIUM (symbol Ge, atomic weight 72.5); one of the metallic elements included in the same natural family as carbon, silicon, tin and lead.

    0
    0
  • SULPHUR [[[symbol]] S, atomic weight 32.07 (0 = 16)], a non-metallic chemical element, known from very remote times and regarded by the alchemists, on account of its inflammable nature, as the principle of combustion; it is also known as brimstone.

    0
    0
  • The laws of chemical combination were solved, in a measure, by John Dalton, and the solution expressed as Dalton's " atomic theory."

    0
    0
  • In place of the relative molecular weights, attention was concentrated on relative atomic or equivalent weights.

    0
    0
  • Torbern Olof Bergman used an elaborate system in his Opuscula physica et chemica (1783); the 1 Dalton's atomic theory is treated in more detail in the article Atom.

    0
    0
  • Mitscherlich in 1820; and he confirmed his conclusions by showing the agreement with the law of atomic heat formulated by Dulong and Petit in 1819.

    0
    0
  • Chemists gradually tired of the notion of atomic weights on account of the uncertainty which surrounded them; and the suggestion made by W.

    0
    0
  • At the conclusion of the sitting, Lothar Meyer obtained a paper written by Stanislas Cannizzaro in 1858 wherein was found the final link required for the determination of atomic weights.

    0
    0
  • This generalization was of great value inasmuch as it permitted the deduction of the atomic weight of a non-gasifiable element from a study of the densities of its gasifiable compounds.

    0
    0
  • From the results obtained by Laurent and Gerhardt and their predecessors it immediately followed that, while an element could have but one atomic weight, it could have several equivalent weights.

    0
    0
  • The solution came abOut by arranging the elements in the order of their atomic weights, tempering the arrangement with the results deduced from the theory of valencies and experimental observations.

    0
    0
  • Elements.-The following table gives the names, symbols and atomic weights of the perfectly characterized elements: International Atomic Weights, 1910.

    0
    0
  • 1 Approximate values of the atomic weights are employed here.

    0
    0
  • Considerable uncertainty existed as to the atomic weights of these metals, the values obtained by Berzelius being doubtful.

    0
    0
  • According to Gerhardt, the process of substitution consisted of the union of two residues to fo- m a unitary whole; these residues, previously termed " compound radicals," are atomic complexes which remain over from the interaction of two compounds.

    0
    0
  • By the indirect method Kopp derived the following atomic volumes: C. 0.

    0
    0
  • These values, however, require modification in certain cases, for discrepancies occur which can be reconciled in some cases by assuming that the atomic value of a polyvalent element varies according to the distribution of its valencies.

    0
    0
  • Recent researches have shown that the law originally proposed by Kopp - " That the specific volume of a liquid compound (molecular volume) at its boiling-point is equal to the sum of the specific volumes of its constituents (atomic volumes), and that every element has a definite atomic value in its compounds " - is by no means exact, for isomers have different specific volumes, and the volume for an increment of CH 2 in different homologous series is by no means constant; for example, the difference among the esters of the fatty acids is about 57, whereas for the aliphatic aldehydes it is 49.

    0
    0
  • The relation between the atomic volumes and the atomic weights of the solid elements exhibits the periodicity which generally characterizes the elements.

    0
    0
  • Similarly, greater atomic complexity is reflected in a further decrease in the ratio C y /Cy.

    0
    0
  • The following table gives a comparative view of the specific heats and the ratio for molecules of variable atomic content.

    0
    0
  • Specific Heats of Solids.-The development of the atomic theory and the subsequent determination of atomic weights in the opening decades of the 19th century inspired A.

    0
    0
  • Dulong to investigate relations (if any) existing between specific heats and the atomic weight.

    0
    0
  • This states that " the atomic heat (the product of the atomic weight and specific heat) of all elements is a constant quantity."

    0
    0
  • This law-purely empirical in origin-was strengthened by Berzelius, who redetermined many specific heats, and applied the law to determine the true atomic weight from the equivalent weight.

    0
    0
  • Weber, who showed that with rise of temperature the specific (and atomic) heat increases, finally attaining a fairly constant value; diamond, graphite and the various amorphous forms of carbon having the value about 5.6 at moo°, and silicon 5.68 at 232°; while he concluded that boron attained a constant value of 5.5.

    0
    0
  • Nilson and Pettersson's observations on beryllium and germanium have shown that the atomic heats of these metals increase with rise of temperature, finally becoming constant with a value 5.6.

    0
    0
  • Trans., 1900, p. 233) investigated nickel and cobalt over a wide range of temperature (from -182.5° to loo°); his results are: It is evident that the atomic heats of these intimately associated elements approach nearer and nearer as we descend in temperature, approximating to the value 4.

    0
    0
  • Other metals were tested in order to determine if their atomic heats approximated to this value at low temperatures, but with negative results.

    0
    0
  • Since the atomic heat of the same element varies with its state of aggregation, it must be concluded that some factor taking this into account must be introduced; moreover, the variation of specific heat with temperature introduces another factor.

    0
    0
  • Trans., 1904, 203 A, p. 139) for those elements whose atomic heats vary considerably with temperature.

    0
    0
  • Conversely, if the specific heats of a compound and its constituent elements, except one, be known, then the unknown atomic heat is readily deducible.

    0
    0
  • Similarly, by taking the difference of the molecular heats of compounds differing by one constituent, the molecular (or atomic) heat of this constituent is directly obtained.

    0
    0
  • - Denoting the atomic weight by W and the specific heat by s, Dulong and Petit's law states that 6.4 = Ws.

    0
    0
  • In the determination of the atomic weight of an element two factors must be considered: (I) its equivalent weight, i.e.

    0
    0
  • The equivalent weight is capable of fairly ready determination, but the settlement of the second factor is somewhat more complex, and in this direction the law of atomic heats is of service.

    0
    0
  • To take an example: 38 parts of indium combine with 35.4 parts of chlorine; hence, if the formula of the chloride be InCI, InC1 2 or InC1 3, indium has the atomic weights 38, 76 or 114.

    0
    0
  • The specific heat of indium is o 057; and the atomic heats corresponding to the atomic weights 38, 76 and 114 are 3.2, 4.3, 6.5.

    0
    0
  • C. Winkler decided the atomic weight of germanium by similar reasoning.

    0
    0
  • Although establishing certain general relations between atomic and molecular refractions, the results were somewhat vitiated by the inadequacy of the empirical function which he employed, since it was by no means a constant which depended only on the actual composition of the substance and was independent of its physical condition.

    0
    0
  • Atomic refractions may be obtained either directly, by investigating the various elements, or indirectly, by considering differences in the molecular refractions of related compounds.

    0
    0
  • The second method proceeds on the same lines as adopted for atomic volumes.

    0
    0
  • Similarly, by this method of differences, the atomic refraction of any element may be determined.

    0
    0
  • It is found, however, that the same element has not always the same atomic refraction, the difference being due to the nature of the elements which saturate its valencies.

    0
    0
  • A table of the atomic refractions and dispersions of the principal elements is here given: Dispersion and Composition.-In the preceding section we have seen that substances possess a definite molecular (or atomic) refraction for light of particular wave-length; the difference between the refractions for any two rays is known as the molecular (or atomic) dispersion.

    0
    0
  • He also showed how changes in constitution effected dispersions to a far greater extent than they did refractions; thus, while the atomic dispersion of carbon is 0.039, the dispersions due to a double and treble linkage is 0.23 and 0.19 respectively.

    0
    0
  • This fact finds a parallel in the atomic weights of these metals.

    0
    0
  • If the crystal structure be regarded as composed of 0 three interpenetrating point systems, one consisting of sulphur atoms, the second of four times as many oxygen atoms, and the third of twice as many potassium atoms, the systems being so arranged that the sulphur system is always centrally situated with respect to the other two, and the potassium system so that it would affect the vertical axis, then it is obvious that the replacement of potassium by an element of greater atomic weight would specially increase the length of w (corresponding to the vertical axis), and cause a smaller increase in the horizontal parameters (x and 1/ '); moreover, the increments would advance with the atomic weight of the replacing metal.

    0
    0
  • If, on the other hand, the sulphur system be replaced by a corresponding selenium system, an element of higher atomic weight, it would be expected that a slight increase would be observed in the vertical parameter, and a greater increase recorded equally in the horizontal parameters.

    0
    0
  • after 360), the great philosopher and founder, with Leucippus, of the atomic theory, was also the author of a map of the inhabited world which he supposed to be half as long again from west to east, as it was broad.

    0
    0
  • NITROGEN [[[symbol]] N., atomic weight 14.

    0
    0
  • Numerous determinations of the atomic weight of nitrogen have been made by different observers, the values obtained varying somewhat according to the methods used.

    0
    0
  • Guye has given a critical discussion of the relative accuracy of the gravimetric and physico-chemical methods, and favours the latter, giving for the atomic weight a value less than 14.01.

    0
    0
  • ERBIUM (symbol, Er; atomic weight, 165-166), one of the metals of the rare earths.

    0
    0
  • While determining its atomic weight, he thought it desirable, for the sake of accuracy, to weigh it in a vacuum, and even in these circumstances he found that the balance behaved in an anomalous manner, the metal appearing to be heavier when cold than when hot.

    0
    0
  • plumbum), and atomic weight 207.10 (o=16).

    0
    0
  • The atomic weight, determined by G.

    0
    0
  • So far, the best results have been attained with aluminium, and the permeability was greatest when the percentages of manganese and aluminium were approximately proportional to the atomic weights of the two metals.

    0
    0
  • Manganese, though belonging (with chromium) to the iron group of metals, is commonly classed as a paramagnetic, its susceptibility being very small in comparison with that of the recognized ferromagnetics; but it is remarkable that its atomic susceptibility in solutions of its salts is even greater than that of iron.

    0
    0
  • Sitz., 1897, 106, II.a, p. 623, and 1898, 107, II.a, p. 5) the atomic susceptibilities k of the metals nickel, chromium, iron, cobalt and manganese in solutions of their salts are as follows: - Fe(i) is iron contained in FeC1 2 and Fe(2) iron contained in Fe2(NOs)s.

    0
    0
  • Thus a relation between susceptibility and atomic weight is clearly indicated.

    0
    0
  • The values assigned to the atomic susceptibilities of most of the known elements are appended.

    0
    0
  • According to the notation adopted by Meyer the atomic susceptibility k=KX atomic-weight/ (density X 1000).

    0
    0
  • Among other researches relating to atomic and molecular magnetism are those of 0.

    0
    0
  • Diamagnetism, in short, is an atomic phenomenon; paramagnetism and ferromagnetism are molecular phenomena.

    0
    0
  • COLUMBIUM, or Niobium (symbol Cb or Nb, atomic weight 94), one of the metallic elements of the nitrogen group, first detected in 1801 by C. Hatchett in a specimen of columbite (niobite) from Massachusetts (Phil.

    0
    0
  • The atomic weight was determined by C. Marignac (Ann.

    0
    0
  • URANIUM [[[symbol]] U, atomic weight 238.5 (0=16)], a metallic chemical element.

    0
    0
  • Peligot's results, though called in question by Berzelius, have been amply confirmed by all subsequent investigators; only now, on theoretical grounds, first set forth by Mendeleeff, we double Peligot's atomic weight, so that U now signifies 240 parts of uranium, while UO 3 stands as the formula of the yellow oxide, and UO 2 as that of Berzelius's metal.

    0
    0
  • Marignac's name is well known for the careful and exact determinations of atomic weights which he carried out for twenty-eight of the elements.

    0
    0
  • stannum, whence the chemical symbol "Sn"; atomic weight =117.6, 0= 16), a metallic chemical element.

    0
    0
  • In the third book he applies the principles of the atomic philosophy to explain the nature of the mind and vital principle, with the view of showing that the soul perishes with the body.

    0
    0
  • Unable to accept Berzelius's doctrine of the unalterability of organic radicals, he also gave a new interpretation to the meaning of copulae under the influence of his fellow-worker Edward Frankland's conception of definite atomic saturation-capacities, and thus contributed in an important degree to the subsequent establishment of the structure theory.

    0
    0
  • SILICON [[[symbol]] Si, atomic weight 28.3 (0=16)], a nonmetallic chemical element.

    0
    0
  • The atomic weight of silicon has been determined usually by analysis of the halide compounds or by conversion of the halides into silica.

    0
    0
  • The general result is that, conformably with Dulong and Petit's law, the "atomic heats" all come to very nearly the same value (of about 6.4); i.e.

    0
    0
  • atomic weight by specific heat = 6.4.

    0
    0
  • In 1850 he published a tragedy, Galileo Galilei, and two volumes of his Lectures on the Atomic Theory and Essays Scientific and Literary appeared in 1858, with a preface by his kinsman Dr John Brown, the author of Horae Subsecivae.

    0
    0
  • ZINC, a metallic chemical element; its symbol is Zn, and atomic weight 65.37 (0= 16).

    0
    0
  • At first this work was merely a compilation, but in the later editions many of his original results were incorporated; the third edition (1807) is noteworthy as containing the first detailed account of the atomic theory, communicated to him by John Dalton himself.

    0
    0
  • TITANIUM [[[symbol]] Ti, atomic weight 48.

    0
    0
  • Rose determined the atomic weight to be 47.72 (H =1).

    0
    0
  • In the following year appeared his Introduction to the Atomic Theory, which was succeeded by a supplement in 1840, and in 1850 by a second edition.

    0
    0
  • STRONTIUM [[[Symbol]] Sr, atomic weight 87.62 (0 = 16)], a metallic chemical element belonging to the alkaline earth group. It is found in small quantities very widely distributed in various rocks and soils, and in mineral waters; its chief sources are the minerals strontianite, celestine and barytocelestine.

    0
    0
  • Recent determinations of the atomic weight of strontium are due to T.

    0
    0
  • It has also been stated that alloys of metals with similar meltingpoints have higher tenacity when the atomic volumes of the constituent metals differ than when they are nearly the same.

    0
    0
  • GOLD [[[symbol]] Au, atomic weight 1 95.7(11 = I),197 2(O =16)], a metallic chemical element, valued from the earliest ages on account of the permanency of its colour and lustre.

    0
    0
  • The atomic weight of gold was first determined with accuracy by Berzelius, who deduced the value 195.7 (H= i) from the amount of mercury necessary to precipitate it from the chloride, and 195.2 from the ratio between gold and potassium chloride in potassium aurichloride, KAuC1 4.

    0
    0
  • Rutherford had announced the nuclear theory of atomic structure which required each atom to consist of a minute positively charged nucleus about which negative electrons were distributed.

    0
    0
  • It seems also that the charge would increase with the atomic weight of the element.

    0
    0
  • It had been suggested, and Bohr had adopted this view, that the nuclear charge was equal to the atomic number, i.e.

    0
    0
  • to the number of the element in a complete series of the elements arranged in ascending order, but hitherto no atomic property had been discovered which could be definitely represented by this number.

    0
    0
  • BISMUTH, a metallic chemical element; symbol Bi, atomic weight 208.5 (0 = 16).

    0
    0
  • TELLURIUM [[[Symbol]] Te, atomic weight 127.5 (0=16)], a chemical element, found to a certain extent in nature in the uncombined condition, but chiefly in combination with other metals in the form of tellurides, such, for example, as sylvanite, black tellurium, and tetradymite.

    0
    0
  • A considerable amount of work has been done on determinations of the atomic weight of tellurium, the earlier results giving the value 128.

    0
    0
  • Recent investigations of the atomic weight are due to G.

    0
    0
  • Sci., 1909 (iv.), 28, p. 347) claim to have separated two substances (of atomic weights 126.49 and 128.85 respectively) from tellurium, by fractional precipitation of tellurium chloride with water, but in the opinion of H.

    0
    0
  • TANTALUM [[[symbol]] Ta, atomic weight 181 o (0=16)], a metallic chemical element, sparingly distributed in nature and then almost invariably associated with columbium.

    0
    0
  • Marignac determined the atomic weight to be 181, but Henrichsen and N.

    0
    0
  • CAESIUM (symbol Cs, atomic weight 132.9), one of the alkali metals.

    0
    0
  • The atomic weight of caesium has been determined by the analysis of its chloride and bromide.

    0
    0
  • For the detailed chemical significance of these terms, see Chemistry; and for the atomic theory of the chemist (as distinguished from the atomic or molecular theory of the physicist) see Atom; reference may also be made to the article Matter.

    0
    0
  • The atomic theory is a theory of the constitution of bodies which asserts that they are made up of atoms. The opposite theory is that of the homogeneity and continuity of bodies, and asserts, at least in the case of bodies having no apparent organization, such, for instance, as water, that as we can divide a drop of water into two parts which are each of them drops of water, so we have reason to believe that these smaller drops can be divided again, and the theory goes on to assert that there is nothing in the nature of things to hinder this process of division from being repeated over and over again, times without end.

    0
    0
  • " In ancient times Democritus was the founder of the atomic theory, while Anaxagoras propounded that of continuity, under the name of the doctrine of homoeomeria ('OAotop.pia), or of the similarity of the parts of a body to the whole.

    0
    0
  • From this point of view the atomic doctrine might be regarded as a relic of the old numerical way of conceiving magnitude, and the opposite doctrine of the infinite divisibility of matter might appear for a time the most scientific. The atomists, on the other hand, asserted very strongly the distinction between matter and space.

    0
    0
  • " The opposite school maintained then, as they have always done, 1 It wiII be noted that Clerk Maxwell's " atom " and " atomic theory " have the significance which we now attach to " molecule " and " molecular theory."

    0
    0
  • " Of the different forms of the atomic theory that of R.

    0
    0
  • The difficulty is further diminished when it is proved, as it can be proved, 2 that the modes of energy represented in the atomic spectrum acquire energy so slowly that the atom might undergo collisions with other atoms for centuries before being set into oscillations which would possess an appreciable amount of energy.

    0
    0
  • OSMIUM [[[symbol]] Os., atomic weight 190.9 (0= 16)], in chemistry, a metallic element, found in platinum ore in small particles, consisting essentially of an alloy of osmium and iridium and known as osmiridium.

    0
    0
  • The atomic weight of the metal has been determined by K.

    0
    0
  • ZIRCONIUM [[[symbol]] Zr, atomic weight 90 6 (0= 16)], a metallic chemical element.

    0
    0
  • The atomic weight was determined by Marignac to be 90.03; Bailey (Proc. Roy.

    0
    0
  • Atomic weight.

    0
    0
  • CALCIUM [[[symbol]] Ca, atomic weight 40.0 (0= 16)], a metallic chemical element, so named by Sir Humphry Davy from its occurrence in chalk (Latin calx).

    0
    0
  • FLUORINE (symbol F, atomic weight iv), a chemical element of the halogen group. It is never found in the uncombined condition, but in combination with calcium as fluor-spar CaF2 it is widely distributed; it is also found in cryolite Na3A1F6, in fluor-apatite, CaF 2.3Ca 3 P 2 O 8, and in minute traces in seawater, in some mineral springs, and as a constituent of the enamel of the teeth.

    0
    0
  • The atomic weight of fluorine has been determined by the conversion of calcium, sodium and potassium fluorides into the corresponding sulphates.

    0
    0
  • Gauss, that the definite results attainable by the hypothesis of mutual atomic attractions really reposed on much wider and less special principles - those, namely, connected with the modern doctrine of energy.

    0
    0
  • Since the period, a century ago, when Dalton and his contemporaries constructed from this idea a scientific basis for chemistry, the progress of that subject has been wonderful beyond any conception that could previously have been entertained; and the atomic theory in some form appears to be an indispensable part of the framework of physical science.

    0
    0
  • To make room for these we have to remember that the atomic nucleus has remained entirely undefined and beyond our problem; so that what may occur, say when two molecules come into close relations, is outside physical science - not, however, altogether outside, for we know that when the vital nexus in any portion of matter is dissolved, the atoms will remain, in their number, and their atmospheres, and all inorganic relations, as they were before vitality supervened.

    0
    0
  • It thus appears that the doctrine of atomic material constitution and the doctrine of a universal aether stand to each other in a relation of mutual support; if the scheme of physical laws is to be as precise as observation and measurement appear to make it, both doctrines are required in our efforts towards synthesis.

    0
    0
  • Returning now to the aether, on our present point of view no such complications there arise; it must be regarded as a continuous uniform medium free from any complexities of atomic aggregation, whose function is confined to the transmission of the various types of physical effect between the portions of matter.

    0
    0
  • True electric current arises solely from convection of the atomic charges or electrons; this current is therefore not restricted as to form in any way.

    0
    0
  • A dielectric substance is electrically polarized by a field of electric force, the atomic poles being made up of the displaced positive and negative intrinsic charges in the atom: the polarization per unit volume (f',g',h') may be defined on the analogy of magnetism, and d/dt(f',g',h') thus constitutes true electric current of polarization, i.e.

    0
    0
  • natrium; atomic weight 23.00 (O= r6)], a chemical element belonging to the group of alkali metals.

    0
    0
  • The atomic weight was determined by Stas to be 22.87 (H = i); T.

    0
    0
  • CARBON (symbol C, atomic weight 12), one of the chemical non-metallic elements.

    0
    0
  • Weber (Jahresberichte, 1874, p. 63): - The atomic weight of carbon has been determined by J.

    0
    0
  • POTASSIUM [[[symbol]] K (from kalium), atomic weight 39.114 0=16)], a metallic chemical element, belonging to the group termed the metals of the alkalis.

    0
    0
  • The atomic weight was determined by Stas and more recently by T.

    0
    0
  • The atomic weight of praseodymium is 140.5.

    0
    0
  • IODINE (symbol I, atomic weight 126.92), a chemical element, belonging to the halogen group. Its name is derived from Gr.

    0
    0
  • The atomic weight of iodine was determined by J.

    0
    0
  • Stas, from the analysis of pure silver iodate, and by C. Marignac from the determinations of the ratios of silver to iodine, and of silver iodide to iodine; the mean value obtained for the atomic weight being 126.53.

    0
    0
  • In 1815 he published anonymously in the Annals of Philosophy a paper "On the relation between the specific gravities of bodies in their gaseous state and the weights of their atoms," in which he calculated that the atomic weights of a number of the elements are multiples of that of hydrogen; and in a second paper published in the same periodical the following year he suggested that the rrpcbrn iiXrl of the ancients is realized in hydrogen, from which the other elements are formed by some process of condensation or grouping.

    0
    0
  • This view, generally known as "Prout's hypothesis," at least had the merit of stimulating inquiry, and many of the most careful determinations of atomic weights undertaken since its promulgation have been provoked by the desire to test its validity.

    0
    0
  • Various chemists had traced numerical sequences among the atomic weights of some of the elements and noted connexions between them and the properties of the different substances; but it was left to him to give a full expression to the generalization, and to treat it not merely as a system of classifying the elements according to certan observed facts, but as a "law of nature" which could be relied upon to predict new facts and to disclose errors in what were supposed to be old facts.

    0
    0
  • Again, in several cases he ventured to question the correctness of the "accepted atomic weights," on the ground that they did not correspond with the Periodic Law, and here also he was justified by subsequent investigation.

    0
    0
  • In 1902, in an "attempt at a chemical conception of the ether," he put forward the hypothesis that there are in existence two elements of smaller atomic weight than hydrogen, and that the lighter of these is a chemically inert, exceedingly mobile, all-penetrating and all-pervading gas, which constitutes the aether.

    0
    0
  • Mendeleeff also devoted much study to the nature of such "indefinite" compounds as solutions, which he looked upon as homogeneous liquid systems of unstable dissociating compounds of the solvent with the substance dissolved, holding the opinion that they are merely an instance of ordinary definite or atomic compounds, subject to Dalton's laws.

    0
    0
  • In his earlier years he devoted himself to chemistry, both theoretical and applied, publishing papers on the preparation of gold and platinum, numerical relations between the atomic weights of analogous elements, the formation of aventurine glass, the manufacture of illuminating gas from wood, the preservation of oil-paintings, &c. The reaction known by his name for the detection of bile acids was published in 1844.

    0
    0
  • Towards the end of his life he adopted the view that the elements have been formed by some process of condensation from one primordial substance of extremely small atomic weight, and he expressed the conviction that atomic weights within narrow limits are variable and modified according to the physical conditions in which a compound is formed.

    0
    0
  • atomic weight 52.1), one of the metallic chemical elements, the name being derived from the fine colour (Gr.

    0
    0
  • The atomic weight of chromium has been determined by S.

    0
    0
  • Roughly speaking the difference in frequency is proportional to the square of the atomic weight.

    0
    0
  • The roots of the three series have frequencies which diminish as the atomic weight increases, but not according to any simple law.

    0
    0
  • The one endeavours to determine the conditions, which are consistent with our knowledge of atomic constitution derived from other sources, and lead to systems of vibration similar to those of the actual atom.

    0
    0
  • Leaving the consideration of radical changes of a vibrating system out of account for the present, the minor differences which have been observed in the appearances of spectra under different sparking conditions are probably to a large extent due to differences in the quantities of material examined, though temperature must alter the violence of the impact and there is a possible effect due to a difference in the impact according as the vibrating system collides with an electron or with a body of atomic dimensions.

    0
    0
  • The velocities ranged from about 400 to 1900 metres, the metals of small atomic weight giving as a rule the higher velocities.

    0
    0
  • As the atomic weight of the haloid increases the spectrum is displaced towards the red.

    0
    0
  • MAGNESIUM [[[symbol]] Mg, atomic weight 24.32 (0 = 16)], a metallic chemical element.

    0
    0
  • The atomic weight of magnesium has been determined by many observers.

    0
    0
  • Chsm., 1850, 50, p. 358), by ignition of the carbonate, obtained the value 24.00 for the atomic weight, whilst C. Marignac, by converting the oxide into the sulphate, obtained the value 24.37.

    0
    0
  • (a) He identifies matter with mind by identifying atomic force with the striving of unconscious will after objects conceived by unconscious intelligence, and by defining causality as logical necessity receiving actuality through will.

    0
    0
  • (b) He contends that, when matter ascends to the evolution of organic life, the unconscious has a power, over and above its atomic volitions, of introducing a new element, and that in consequence the facts of variation, selection and inheritance, pointed out by Darwin, are merely means which the unconscious uses for its own ends in morphological development.

    0
    0
  • EUROPIUM, a metallic chemical element, symbol Eu, atomic weight 152 0 (0 =16).

    0
    0
  • But the most important of all Dalton's investigations are those concerned with the Atomic Theory in chemistry, with which his name is inseparably associated.

    0
    0
  • But from a study of Dalton's own MS. laboratory notebooks, discovered in the rooms of the Manchester society, Roscoe and Harden (A New View of the Origin of Dalton's Atomic Theor y, 1896) conclude that so far from Dalton being led to the idea that chemical combination consists in the approximation of atoms of definite and characteristic weight by his search for an explanation of the law of combination in multiple proportions, the idea of atomic structure arose in his mind as a purely physical conception, forced upon him by study of the physical properties of the atmosphere and other gases.

    0
    0
  • He proceeds to give what has been quoted as his first table of atomic weights, but on p. 248 of his laboratory notebooks for 1802-1804, under the date 6th of September 1803, there is an earlier one in which he sets forth the relative weights of the ultimate atoms of a number of substances, derived from analysis of water, ammonia, carbon-dioxide, &c. by chemists of the time.

    0
    0
  • Dalton communicated his atomic theory to Dr Thomson, who by consent included an outline of it in the third edition of his System of Chemistry (1807), and Dalton gave a further account of it in the first part of the first volume of his New System of Chemical Philosophy (1808).

    0
    0
  • He took the same course soon afterwards with four other papers, two of which - "On the quantity of acids, bases and salts in different varieties of salts" and "On a new and easy method of analysing sugar," contain his discovery, regarded by him as second in importance only to the atomic theory, that certain anhydrous salts when dissolved in water cause no increase in its volume, his inference being that the "salt enters into the pores of the water."

    0
    0
  • Thus he distrusted, and probably never fully accepted, Gay-Lussac's conclusions as to the combining volumes of gases; he held peculiar and quite unfounded views about chlorine, even after its elementary character had been settled by Davy; he persisted in using the atomic weights he himself had adopted, even when they had been superseded by the more accurate determinations of other chemists; and he always objected to the chemical notation devised by J.

    0
    0
  • Before he had propounded the atomic theory he had already attained a considerable scientific reputation.

    0
    0
  • See Henry, Life of Dalton, Cavendish Society (1854); Angus Smith, Memoir of John Dalton and History of the Atomic Theory (1856), which on pp. 253-263 gives a list of Dalton's publications; and Roscoe and Harden, A New View of the Origin of Dalton's Atomic Theory (1896); also Atom.

    0
    0
  • ALUMINIUM (symbol Al; atomic weight 27.0), a metallic chemical element.

    0
    0
  • Deville accordingly returned to pure chemistry and invented a practicable method of preparing sodium which, having a lower atomic weight than potassium, reduced a larger proportion.

    0
    0
  • Its atomic weight is 27 (26.77, H=I, according to J.

    0
    0
  • He published many physical memoirs on electricity, the dilatation of liquids by heat, specific heats, capillary attraction, atomic volumes &c. as well as a treatise in 4 volumes on Fisica di corpi ponderabili (1837-1841).

    0
    0
  • so much of either metal as is present in excess over the eutectic ratio, freezes out before the eutectic; (2) that though thus constant, its composition is not in simple atomic proportions; (3) that its freezing-point is constant; and (4) that, when first formed, it habitually consists of interstratified plates of the metals which compose it.

    0
    0
  • It is the last part of the metal to undergo this transformation and, when thus transformed, it is of constant though not atomic composition, and habitually consists of interstratified plates of its component metals.

    0
    0
  • HYDROGEN [[[symbol]] H, atomic weight 1 o08 (o=16)], one of the chemical elements.

    0
    0
  • These phenomena were quite in accordance with the atomic conception of matter, since a compound containing the same number of atoms of carbon, nitrogen, oxygen and hydrogen as another in the same weight might differ in internal structure by different arrangements of those atoms. Even in the time of Berzelius the newly introduced conception proved to include two different groups of facts.

    0
    0
  • that atoms attached to carbon, to express it in the atomic style, cling more intensely to it than, for instance, when combined with oxygen.

    0
    0
  • Now, in this case, the first definition expresses much better the whole chemical behaviour of ozone, which is that of "energetic" oxygen, while the second only includes the fact of higher vapour-density; but in applying the first definition to organic compounds and calling isobutylene "butylene with somewhat more energy" hardly anything is indicated, and all the advantages of the atomic conception - the possibility of exactly predicting how many isomers a given formula includes and how you may get them - are lost.

    0
    0
  • The spectrum, also, is very characteristic. The atomic weight, 226.4, places the element in a vacant position in group II.

    0
    0
  • LANTHANUM [[[symbol]] La, atomic weight 139.0 (0=16)] one of the metals of the cerium group of rare earths.

    0
    0
  • It is decomposed by water with the formation of acetylene, methane, ethylene, &c. Lanthanum carbonate, La 2 CO 3 8H 2 O, occurs as the rare mineral lanthanite, forming greyish-white, pink or yellowish rhombic prisms. The atomic weight of lanthanum has been determined by B.

    0
    0
  • BERYLLIUM, or Glucinum (symbol Be, atomic weight 9.1), one of the metallic chemical elements, included in the same sub-group of the periodic classification as magnesium.

    0
    0
  • Its atomic weight has been determined by L.

    0
    0
  • Hence during the day the assimilatory processes of these cells are overbalanced by their wear and tear, and the end-result is that the cell attains an atomic condition less favourable to further disintegration than to reintegration.

    0
    0
  • THALLIUM [[[symbol]] Tl, atomic weight 204.0 (0 = 16)], a metallic chemical element.

    0
    0
  • The atomic weight of thallium was determined very carefully by Crookes, who found T1=204.2 (0= 16); this figure was confirmed by Lepierre in 1893.

    0
    0
  • H.*) 0 Xygen (symbol 0, atomic weight 16), a non-metallic chemical element.

    0
    0
  • The atomic weight of oxygen is now generally taken as 16, and as such is used as the standard by which the atomic weights of the other elements are determined, owing to the fact that most elements combine with oxygen more readily than with hydrogen (see ELE Ment).

    0
    0
  • MANGANESE [[[symbol]] Mn; atomic weight, 54.93 (0 = t6)], a metallic chemical element.

    0
    0
  • The atomic weight of manganese has been frequently determined.

    0
    0
  • CERIUM (symbol Ce, atomic weight 140.25), a metallic chemical element which occurs with the rare earths in the minerals cerite, samarskite, euxenite, monazite, parisite and many yttrium minerals.

    0
    0
  • The atomic weight of cerium has been determined by B.

    0
    0
  • SCANDIUM [[[symbol]] Sc, atomic weight 44.1 (0=16)1, one of the rare earth metals.

    0
    0
  • GALLIUM (symbol Ga; atomic weight 69.9), one of the metallic chemical elements.

    0
    0
  • The atomic weight of gallium has been determined by Lecoq de Boisbaudran by ignition of gallium ammonium alum, and also by L.

    0
    0
  • From An M Atomic Molecule We Should Then Have S/S= 2/(2M I).

    0
    0
  • Atomic And Molecular Heats.

    0
    0
  • The Ideal Atomic Heat Is The Thermal Capacity Of A Gramme Atom In The Ideal State Of Monatomic Gas At Constant Volume.

    0
    0
  • For A Diatomic Gas, The Molecular Heat Would Be Nearly Five Calories, Or The Atomic Heat Of A Gas In The Diatomic State Would Be 2.5.

    0
    0
  • Estimated At Constant Pressure The Atomic Heat Would Be 3.5.

    0
    0
  • Some Authors Adopt 2.5 And Some 3.5 For The Ideal Atomic Heat.

    0
    0
  • The Atomic Heat Of A Metal In The Solid State Is In Most Cases Larger Than Six Calories At Ordinary Temperatures.

    0
    0
  • Considering The Wide Variations In The Physical Condition And Melting Points, The Comparatively Close Agreement Of The Atomic Heats Of The Metals At Ordinary Temperatures, Known As Dulong And Petit'S Law, Is Very Remarkable.

    0
    0
  • Trans., 1900), The Atomic Heats Of Pure Nickel And Cobalt, As Determined From Experiments At The Boiling Points Of 02, And C02, Diminish So Rapidly At Temperatures Below O° C. As To Suggest That They Would Reach The Value 2.42 At The Absolute Zero.

    0
    0
  • This Is The Value Of The Minimum Of Atomic Heat Calculated By Perry From Diatomic Hydrogen, But The Observations Themselves Might Be Equally Well Represented By Taking The Imaginary Limit 3, Since The Quantity Actually Observed Is The Mean Specific Heat Between O° And 182 5° C. Subsequent Experiments On Other Metals At Low Temperatures Did Not Indicate A Similar Diminution Of Specific Heat, So That It May Be Doubted Whether The Atomic Heats Really Approach The Ideal Value At The Absolute Zero.

    0
    0
  • No Doubt There Must Be Approximate Relations Between The Atomic And Molecular Heats Of Similar Elements And Compounds, But Considering The Great Variations Of Specific Heat With Temperature And Physical State, In Alloys, Mixtures Or Solutions, And In Allotropic Or Other Modifications, It Would Be Idle To Expect That The Specific Heat Of A Compound Could Be Accurately Deduced By Any Simple Additive Process From That Of Its Constituents.

    0
    0
  • 'THORIUM (symbol Th, atomic weight 232.42 [0 = 16]), a metallic chemical element.

    0
    0
  • He concluded that the first contained the chloride of berzelium, having an atomic weight of 212, the second contained thorium chloride, and the third the chloride of carolinium, having an atomic weight of 255.6.

    0
    0
  • The atomic weight has been variously given.

    0
    0
  • NICKEL (symbol Ni, atomic weight 58.68 (0 =16)), a metallic element.

    0
    0
  • Numerous determinations of the atomic weight of nickel have been published, the values obtained varying from 58 o to approximately 59.5 The more recent work of T.

    0
    0
  • News, 18 99, 79, 163, 174, 185) gives for the atomic weight of the metal the values 58.69 and 58.70.

    0
    0
  • They are the atomic elements which " the workmanship of the understanding " can thereafter do no more than systematically compound and the like.

    0
    0
  • RUBIDIUM [[[symbol]] Rb, atomic weight 85.45 (0= 16)], a metallic element belonging to the group of the alkali metals.

    0
    0
  • The atomic weight of rubidium was determined by R.

    0
    0
Browse other sentences examples →