Atomic sentence example
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.
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.
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.
The atomic weight of the element has been determined by analysis.
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.Advertisement
The atomic weight was determined by Cleve.
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.
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.
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.
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.Advertisement
As the atomic weight of the element increases, it is found that the solubility of the sulphates in water decreases.
The neutralization of acids by bases affords many illustrations, known even before the atomic theory, of the truth of the statement.
The atomic weight of cadmium was found by 0.
That was indeed the hope for atomic energy in that era, and it did not pan out.
As Dalton said, "The doctrine of definite proportions appears mysterious unless we adopt the atomic hypothesis."Advertisement
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.
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.
Many varying values have been given for the atomic weight of molybdenum.
The atomic weight was determined by Berzelius, Erdmann and Marchand, Dumas and Stas.
Apart from the atomic theory there is no obvious reason why this should be so.Advertisement
The question is, however, vital to the atomic theory.
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.
The discovery of this law is due to Dalton; it is a direct deduction from his atomic theory.
In place of the relative molecular weights, attention was concentrated on relative atomic or equivalent weights.
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.Advertisement
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.
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.
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.
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.
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.Advertisement
Considerable uncertainty existed as to the atomic weights of these metals, the values obtained by Berzelius being doubtful.
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.
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.
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.
The relation between the atomic volumes and the atomic weights of the solid elements exhibits the periodicity which generally characterizes the elements.Advertisement
Similarly, greater atomic complexity is reflected in a further decrease in the ratio C y /Cy.
The following table gives a comparative view of the specific heats and the ratio for molecules of variable atomic content.
Dulong to investigate relations (if any) existing between specific heats and the atomic weight.
This states that " the atomic heat (the product of the atomic weight and specific heat) of all elements is a constant quantity."
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.Advertisement
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.
Other metals were tested in order to determine if their atomic heats approximated to this value at low temperatures, but with negative results.
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.
Conversely, if the specific heats of a compound and its constituent elements, except one, be known, then the unknown atomic heat is readily deducible.
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.Advertisement
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.
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.
C. Winkler decided the atomic weight of germanium by similar reasoning.
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.
Atomic refractions may be obtained either directly, by investigating the various elements, or indirectly, by considering differences in the molecular refractions of related compounds.Advertisement
The second method proceeds on the same lines as adopted for atomic volumes.
Similarly, by this method of differences, the atomic refraction of any element may be determined.
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.
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.
This fact finds a parallel in the atomic weights of these metals.
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.
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.
Numerous determinations of the atomic weight of nitrogen have been made by different observers, the values obtained varying somewhat according to the methods used.
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.
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.
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.
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.
Thus a relation between susceptibility and atomic weight is clearly indicated.
The values assigned to the atomic susceptibilities of most of the known elements are appended.
According to the notation adopted by Meyer the atomic susceptibility k=KX atomic-weight/ (density X 1000).
Among other researches relating to atomic and molecular magnetism are those of 0.
Diamagnetism, in short, is an atomic phenomenon; paramagnetism and ferromagnetism are molecular phenomena.
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.
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.
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.
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.
The atomic weight of silicon has been determined usually by analysis of the halide compounds or by conversion of the halides into silica.
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.
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.
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.
Rose determined the atomic weight to be 47.72 (H =1).
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.
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.
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.
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.
It seems also that the charge would increase with the atomic weight of the element.
It had been suggested, and Bohr had adopted this view, that the nuclear charge was equal to the atomic number, i.e.
A considerable amount of work has been done on determinations of the atomic weight of tellurium, the earlier results giving the value 128.
The atomic weight of caesium has been determined by the analysis of its chloride and bromide.
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.
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.
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.
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.
The atomic weight of fluorine has been determined by the conversion of calcium, sodium and potassium fluorides into the corresponding sulphates.
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.
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.
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.
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.
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.
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.
The atomic weight of praseodymium is 140.5.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Roughly speaking the difference in frequency is proportional to the square of the atomic weight.
The roots of the three series have frequencies which diminish as the atomic weight increases, but not according to any simple law.
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.
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.
The velocities ranged from about 400 to 1900 metres, the metals of small atomic weight giving as a rule the higher velocities.
As the atomic weight of the haloid increases the spectrum is displaced towards the red.
The atomic weight of magnesium has been determined by many observers.
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.
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.
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.
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).
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."
Before he had propounded the atomic theory he had already attained a considerable scientific reputation.
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.
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.
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).
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.
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.
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.
The spectrum, also, is very characteristic. The atomic weight, 226.4, places the element in a vacant position in group II.
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.
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.
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).
The atomic weight of manganese has been frequently determined.
From An M Atomic Molecule We Should Then Have S/S= 2/(2M I).
The Ideal Atomic Heat Is The Thermal Capacity Of A Gramme Atom In The Ideal State Of Monatomic Gas At Constant Volume.
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.
Estimated At Constant Pressure The Atomic Heat Would Be 3.5.
Some Authors Adopt 2.5 And Some 3.5 For The Ideal Atomic Heat.
The Atomic Heat Of A Metal In The Solid State Is In Most Cases Larger Than Six Calories At Ordinary Temperatures.
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.
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.
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.
The atomic weight has been variously given.
They are the atomic elements which " the workmanship of the understanding " can thereafter do no more than systematically compound and the like.
The atomic weight has been determined by many investigators; the chief methods employed being the analysis and synthesis of the trioxide and the analysis of the hexachloride.
Thus, as the atomic weight increases, the state of aggregation changes from that of a gas in the case of fluorine and chlorine, to that of a liquid (bromine) and finally to that of the solid (iodine); at the same time the melting and boiling points rise with increasing atomic weights.
The halogen of lower atomic weight can displace one of higher atomic weight from its hydrogen compound, or from the salt derived from such hydrogen compound, while, on the other hand, the halogen of higher atomic weight can displace that of lower atomic weight, from the halogen oxy-acids and their salts; thus iodine will liberate chlorine from potassium chlorate and also from perchloric acid.
All four of the halogens unite with hydrogen, but the affinity for hydrogen decreases as the atomic weight increases, hydrogen and fluorine uniting explosively at very low temperatures and in the dark, whilst hydrogen and iodine unite only at high temperatures, and even then the resulting compound is very readily decomposed by heat.
On the other hand the stability of the known oxygen compounds increases with the atomic weight, thus iodine pentoxide is, at ordinary temperatures, a well-defined crystalline solid, which is only decomposed on heating strongly, whilst chlorine monoxide, chlorine peroxide, and chlorine heptoxide are very unstable, even at ordinary temperatures, decomposing at the slightest shock.
In a third, " On some important points in the theory of heat " (1819), they stated that the specific heats of thirteen solid elements which they had investigated were nearly proportional to their atomic weights - a fact otherwise expressed in the " law of Dulong and Petit " that the atoms of simple substances have equal capacities for heat.
It was then assumed that each of the two constituents of the neutral fluid had an atomic structure and that the so-called particles of one of the electric fluids, say positive, repelled similar particles with a force varying inversely as a square of the distance and attracted those of the opposite fluid according to the same law.
Furthermore his electrochemical investigations, and particularly his discovery of the important law of electrolysis, that the movement of a certain quantity of electricity through an electrolyte is always accompanied by the transfer of a certain definite quantity of matter from one electrode to another and the liberation at these electrodes of an equivalent weight of the ions, gave foundation for the idea of a definite atomic charge of electricity.
Berzelius early in the 19th century had advanced the hypothesis that chemical combination was due to electric attractions between the electric charges carried by chemical atoms. The notion, however, that electricity is atomic in structure was definitely put forward by Hermann von Helmholtz in a well-known Faraday lecture.
In every solid body there is a continual atomic dissociation, the result of which is that mixed up with the atoms of chemical matter composing them we have a greater or less percentage of free electrons.
Cudworth criticizes two main forms of materialistic atheism, the atomic, adopted by Democritus, Epicurus and Hobbes; and the hylozoic, attributed to Strato, which explains everything by the supposition of an inward self-organizing life in matter.
The atomic weight of antimony has been determined by the analysis of the chloride, bromide and iodide.
Numerous determinations of the atomic weight of selenium have been made.
During his college course he kept note books labelled " The Mind," " Natural Science " (containing a discussion of the atomic theory, &c.), " The Scriptures " and " Miscellanies," had a grand plan for a work on natural and mental philosophy, and drew up for himself rules for its composition.
The atomic weight of phosphorus was determined by Berzelius, Pelouze, Jacquelin, Dumas, Schrotter, Brodie and van der Plaats.
The absence of lines of the spectrum of any element from the solar spectrum is no proof that the element is absent from the sun; apart from the possibility that the high temperature and other circumstances may show it transformed into some unknown mode, which is perhaps the explanation of the absence of nitrogen, chlorine and other non-metals; if the element is of high atomic weight we should expect it to be found only in the lowest strata of the sun's atmosphere, where its temperature was nearly equal to that of the central globe, and so any absorption line which it showed would be weak.
John Brown (1722-1787), a once celebrated dissenting divine, author of the Self-Interpreting Bible, ministered in the burgh for 36 years and is buried there; his son John the theologian (1754-1832), and his grandson Samuel (1817-1856), the chemist, noted for his inquiries into the atomic theory, were natives.
In the following year he published at Vienna his famous work, Theoria philosophiae naturalis redacta ad unicam legem virium in natura existentium, containing his atomic theory (see MOLECULE).
He argues that Hobbes's atomic materialism involves the conception of an objective physical world, the object not of passive sense that varies from man to man, but of the active intellect that is the same in all; there is therefore, he urges, an inconsistency in refusing to admit a similar exercise of intellect in morals, and an objective world of right and wrong, which the mind by its normal activity clearly apprehends as such.
The atomic weight of arsenic has been determined by many different chemists.
A brief paper entitled "Speculative Ideas on the Constitution of Matter" (1863) possesses special interest in connexion with work done since his death, because in it he expressed the view that the various kinds of matter now recognized as different elementary substances may possess one and the same ultimate or atomic molecule in different conditions of movement.
By the theory of minute constituents of things, and his emphasis on mechanical processes in the formation of order, he paved the way for the atomic theory.
In a paper on the atomic theory, published so early as 1826, he anticipated to a remarkable extent some ideas which are frequently supposed to belong to a later period; and the continuation of these studies led him to the ideas about substitution ("metalepsis") which were developed about 1839 into the theory ("Older Type Theory") that in organic chemistry there are certain types which remain unchanged even when their hydrogen is replaced by an equivalent quantity of a haloid element.
In the 1826 paper he described his famous method for ascertaining vapour densities, and the redeterminations which he undertook by its aid of the atomic weights of carbon and oxygen proved the forerunners of a long series which included some thirty of the elements, the results being mostly published in 1858-1860.
He wasn't about to believe Death until he saw Katie for himself. A minute after midnight on the fourth day, if Katie wasn't standing beside him, he'd need the knowledge of where to set off the atomic bomb within him.
Their new atomic arsenal gave them the means to secure this.
Topic locks are used to make store operations atomic.
Nanoscale control of these layers is crucial Ã¢ even atomic level defects cause a problem.
This leads to nuclear power, and also atomic weapons.
Only three days later, the United States dropped a second atomic bomb on Nagasaki.
The second is Iran's efforts to assemble the capability to build an atomic bomb.
It was the invasion of Poland that made Joseph Rotblat suggest to James Chadwick that they should start work on developing an atomic bomb.
Further advances in warfare were to see Carbide collaborate in the Manhattan project to produce the first atomic bomb 25 years later.
The answer to the question has much to do with the question of why the Germans never tried to make an atomic bomb.
The play is set in June 1945, a month before the testing of the first atomic bomb.
Each satellite carries an incredibly accurate atomic clock and broadcasts a regular time signal as well as precise information on its location.
Another 21% of the air is oxygen, with the molecules having an atomic weight of 32.
If the " missile explodes on launchpad " the atomic cannon is destroyed.
The sensor itself is an atomic force microscope cantilever.
An atomic level are only six to competea decade shrimp entrees chowders.
The vault breathed in blue in time with the atomic clock.
The only restriction is that the atomic coordinates are given in Angstroms on arbitrary orthogonal axes.
Atomic chlorine, being heavier, exhibits stronger spin-orbit coupling.
This can only happen by a process of atomic diffusion within the solid.
Atomic level defects, such as atoms of differing mass, vacancies etc. can be introduced by adding dopants or by ion bombardment.
The book's high points are sections relating to what the authors call atomic espionage and the CP Washington spy apparatus.
I can trace my family back to a protoplasmal primordial atomic globule.
Thursday 06 September 2001 good golly, it's Molly POP star wife Kerry Katona has finally had her very own atomic kitten.
An atomic holocaust can begin which will destroy a lot.
A H I nebula is made of neutral atomic hydrogen.
This includes various methods of modifying semiconductor chips at the atomic level for the purpose of fabricating integrated circuits (ICs ).
The set of atomic invariants contains the instances of static predicates which are always true.
Atomic or molecular transitions are often induced by the screened Coulomb potentials of atoms or partially ionized ions.
Only the imagination can overcome the atomic isolation of the individual.
Compounds that have the same formula but differ in their atomic positions, like these two, are called isomers.
Atomic Force Microscopy is employed to study the kinetics of the etching mechanism used to produce the mirror surface.
Generally there is no point providing a solvent mask, since the solvent density generally does not provide a match to atomic features.
A special segment examines the properties of atoms, explaining how atomic mass and atomic numbers are calculated.
Using the sharp tip of an atomic force microscope, nanometer-sized holes will be created on various surfaces.
Atomic resolution is possible using electron microscopes and scanning probe microscopes.
His techniques were an inspiration for early atomic force microscopy.
It is quite a challenge to obtain clear EXAFS signals from samples with a mean thickness of only 12 atomic monolayers.
Atomic clocks are accurate to the nearest nanosecond - equivalent to losing or gaining one second in about 33 years!
Neutron diffraction techniques are employed to investigate both atomic and magnetic structures, while longer range fluctuations are studied using small angle neutron diffraction techniques are employed to investigate both atomic and magnetic structures, while longer range fluctuations are studied using small angle neutron scattering.
A proton in an atomic nucleus has an equal positive charge.
How atomic clocks work The part of an atomic clock which is responsible for keeping time is actually a quartz crystal oscillator.
The two had worked together during the 1920s and revolutionized atomic physics.
A previous year's slide show introducing atomic and nuclear physics is provided in HTML and PowerPoint formats.
Atomic Force Micrograph image of MgO (100) face etched in deionised water showing pyramidal etch pits.
Japan's domestic atomic power program is based on reprocessed plutonium.
The type of atomic radius being measured here is called the metallic radius or the covalent radius depending on the bonding.
Atomic and ionic radius increase down both groups as can be predicted from the increasing number of shells.
When the processes of manifestation start, this homogenous, original, eternally self-existent stuff becomes atomic, differentiated.
From the outset, Washington's atomic program was driven by self-interest.
I was able to get these Mars-Saturn experiment filterpapers analyzed using an atomic absorption spectrophotometer!
There were also a selection of blinders and atomic strobes scattered all over the stage.
Atomic spectra generally consist of many sharp lines which, in the absence of spectral overlap, appear symmetrical.
An atomic clock synchronized to GPS is required in order to compute ranges from these three signals.
However thanks to latest technology, the atomic clock can now be brought into your homes.
Atomic scale characterisation of metal-insulator phase transitions in strongly correlated electron systems.
Russian co-operation could be crucial for keeping Iran's atomic energy industry within the bounds of the non-proliferation treaty.
A second world war might be tolerated, but atomic weaponry?
In the time, however, of Boyle 1 and Newton, we again find an atomic theory of matter; Newton 2 regarded a gas as consisting of small separate particles which repelled one another, the tendency of a gas to expand being attributed to the supposed repulsion between the particles.
It is remarkable that pure chemistry, even to-day, has no very conclusive arguments for the settlement of this controversy; but the sister science of physics is steadily accumulating evidence in favour of the atomic conception.
Until the time of John Dalton, the atomic conception remained purely qualitative, and until then it does not appear to have 1 Robert Boyle, The Sceptical Chymist (1661); The Usefulness of Natural Philosophy (1663).
Dalton (1803) gave the atomic theory a quantitative form, and showed that, by means of it, a vast number of the facts of chemistry could be predicted or explained.
Harden, New View of the Atomic Theory (1896), have shown, from a study of Dalton's manuscript notes, that we do not owe his atomic theory to such experiments.
He thus arrived at the conception of a definite atomic weight peculiar to the particles of each gas, and he thought that he could determine these atomic weights, in terms of one of them, by means of the quantitative analysis of compounds.
This view is clearly inconsistent with the atomic theory, which requires that when the combining ratio of two substances changes it should do so, per saltum, to quite another value.
Stas, that we find the most brilliant and vigorous verification of these laws, and therefore of the atomic theory.
The law of the conservation of matter, an important element in the atomic theory, has been roughly verified by innumerable analyses, in which, a given weight of a substance having been taken, each ingredient in it is isolated and its weight separately determined; the total weight of the ingredients is always found to be very nearly equal to the weight of the original substance.
The two laws discussed above were more or less accepted before the promulgation of the atomic theory, but the law of multiple proportions is the legitimate offspring of this theory.
It will be noticed that the ratio found is sometimes above and sometimes below the number 2, which is required by the atomic theory, and therefore the deviations may not unreasonably be attributed to experimental errors.
To take the simplest possible case, if Dalton had been correct in assuming that the molecule of water was made up of one atom of oxygen and one of hydrogen, then the experimental fact that water contains eight parts by weight of oxygen to one part of hydrogen, would at once show that the atom of oxygen is eight times as heavy as the atom of hydrogen, or that, taking the atomic weight of hydrogen as the unit, the.
Similarly, Dalton's diagram for ammonia, together with the fact that ammonia contains 4.67 parts of nitrogen to one of hydrogen, at once leads to the conclusion that the atomic weight of nitrogen is 4.67.
The symbol, like that of Dalton, always stands for the atomic weight of the element, that is, while H stands for one part by weight of hydrogen, 0 stands for 16 parts of oxygen, and so on.
Thus the symbol or formula H 2 O for water expresses the view that the molecule of water consists of one atom of oxygen and two of hydrogen; and if we know the atomic weights of oxygen and hydrogen, it also tells us the composition of water by weight.
Some distinguished chemists have thought atomic that this fate may be awaiting the atomic theory, and that in future chemists may be able to obtain all the guidance they need from the science of the transformations of energy.
In these salts X = NO 2 and M = one atomic proportion of a monovalent metal, or the equivalent quantity of a divalent metal.
The accepted atomic weight is accordingly double the density, i.e.
The atomic weight of the element was determined by C. Winkler by analysis of the pure chloride GeCl4, the value obtained being 72.32, whilst Lecoq de Boisbaudran (Comptes rend us, 1886, 103, 45 2), by a comparison of the lines in the spark spectrum of the element, deduced the value 72.3.
Newlands in England, that if they are arranged in the order of their atomic weights they fall into groups in which similar chemical and physical properties are repeated at periodic intervals; and in particular he showed that if the atomic weights are plotted as ordinates and the atomic volumes as abscissae, the curve obtained presents a series of maxima and minima, the most electro-positive elements appearing at the peaks of the curve in the order of their atomic weights.
The evolution of the notion of elements is treated under Element; the molecular hypothesis of matter under Molecule; and the genesis of, and deductions from, the atomic theory of Dalton receive detailed analysis in the article Atom.
In the development of the atomic theory and the deduction of the atomic weights of elements and the formulae of compounds, Dalton's arbitrary rules failed to find complete acceptance.
His terminology was vague and provoked caustic criticism from Berzelius; he assumed that all molecules contained two atoms, and consequently the atomic weights deduced from vapour density determinations of sulphur, mercury, arsenic, and phosphorus were quite different from those established by gravimetric and other methods.
He called this proportion the " atom," since it invariably enters compounds without division, and the weight of this atom is the atomic weight.
The development of the atomic theory and its concomitants - the laws of chemical combination and the notion of atoms and equivalents - at the hands of Dalton and Berzelius, the extension to the modern theory of the atom and molecule, and to atomic and molecular weights by Avogadro, Ampere, Dumas, Laurent, Gerhardt, Cannizzaro and others, have been noted.
The atomic theory, and its correlatives - the laws of constant and multiple proportions - had been shown to possess absolute validity so far as well-characterized inorganic compounds were concerned; but it was open to question whether organic compounds obeyed the same laws.
The formulation of the atomic theory by John Dalton gave a fresh impetus to the development of quantitative analysis; and the determination of combining or equivalent weights by Berzelius led to the perfecting of the methods of gravimetric analysis.
Thus the actually observed densities of liquid chlorine and bromine at the boilingpoints are 1 56 and 2-96, leading to atomic volumes 22.7 and 26.9, which closely correspond to Kopp's values deduced from organic compounds.
This subject has been principally investigated by Briihl; he found that molecular dispersions of liquids and gases were independent of temperature, and fairly independent of the state of aggregation, but that no simple connexion exists between atomic refractions and dispersions (see preceding table).
He found that his crystal-grating gave a spectrum of two lines for each element and that their frequency increased by definite steps ashepassed from one element to the next; indeed, the frequency of vibration associated with each element was a simple function of a number which he found to be identical with the atomic number.
According to its position in the periodic classification of the elements one would expect its atomic weight to be less than that of iodine, instead of approximately equal, and on this account many efforts have been made to isolate another element from tellurium compounds, but none have as yet been successful.
As already mentioned, all efforts to assimilate optical propagation to transmission of waves in an ordinary solid medium have failed; and though the idea of regions of intrinsic strain, as for example in unannealed glass, is familiar in physics, yet on account of the absence of mobility of the strain no attempt had been made to employ them to illustrate the electric fields of atomic charges.
Thomson, the successor of Maxwell and Lord Rayleigh in the Cavendish chair of physics in the university of Cambridge, began about the year 1899 a remarkable series of investigations on the cathode discharge, which finally enabled him to make a measurement of the ratio of the electric charge to the mass of the particles of matter projected from the cathode, and to show that this electric charge was identical with the atomic electric charge carried by a hydrogen ion in the act of electrolysis, but that the mass of the cathode particles, or " corpuscles " as he called them, was far less, viz.
Atomic atheism is by far the more important, if only because Hobbes, the great antagonist whom Cudworth always has in view, is supposed to have held it.
In his researches, Roscoe showed that the atomic weight of the metal as determined by Berzelius and the formulae given to the oxides were incorrect, and pointed out that the element falls into its natural place in group V of the periodic classification along with phosphorus and arsenic, and not in the chromium group where it had originally been placed.
A complete description of the EC process is not possible to achieve due to the large number of involved atomic rearrangement pathways.
This criticism of Einstein 's Theory of Relativity by the inventor of the atomic clock is censored in all mainstream scientific publications.
The non-linear correction required to simulate low-energy X-ray photoabsorption is basically important when the scintillator cocktail contains elements of high atomic numbers.
Its surface will be scorched by the fire of the atomic bombs.
To determine heavy atoms such as Selenium atoms in a protein the atomic resolution data is not needed.
The computed density therefore does not correspond to a self-consistent atomic calculation.
From the outset, Washington 's atomic program was driven by self-interest.
I was able to get these Mars-Saturn experiment filterpapers analyzed using an atomic absorption spectrophotometer !
Furthermore more work needs to be done to settle the dispute whether atomic interaction lines can also indicate steric interactions [83 ].
There were also a selection of blinders and Atomic strobes scattered all over the stage.
It generalizes and supersedes classical physics, mainly in the realm of atomic and subatomic phenomena.
The exploration of the atomic and subatomic world brought them in contact with a strange and unexpected reality.
They are right there among other micro events, at atomic and subatomic levels, as distinct from macro events.
Russian co-operation could be crucial for keeping Iran 's atomic energy industry within the bounds of the non-proliferation treaty.
Atomic clocks, in particular, are great for this purpose, since they automatically synchronize with different atomic clocks around the world.
The Atomic Testing Museum is age-appropriate for all and includes interactive displays to entertain and educate.
The Atomic Energy Commission prohibited the use of uranium during and after World War II.
The Atomic STI ski boot collection is an incredibly popular boot for 2010, particularly among world-class racers such as Lara Gut, Marlies Schild, and Kathrin Zettel.
Atomic is one of the world's top ski companies, specializing in everything from skis, boots and bindings, to cross country ski gear.
The company was started in 1955 when Alois Rohrmoser created the first pair of Atomic skis.
Today, Atomic is making great strides in the eco-friendly market with their Renu boot series.
Atomic makes fantastic ski boots and their line only continues to improve with the times.
More advanced levels of physics work with the smallest of sub atomic particles and their reactions to one another.
For most people, the most common retro designs are those influenced by the atomic age of the 1950s.
Choose from chic retro printed fabrics like atomic cherries or sugar hearts.
Black Rain is often used as a reference to the precipitation that fell after Hiroshima Japan was hit by atomic bombs.
Coincidentally, he also assisted in building the first atomic bomb.
The Gypsy Trail Teapot is a great example of some of their best atomic age work.
In fact, their amazing partnering skills account for seven of the top ten ballroom dance scenes in vintage film according to the Atomic Ballroom website.
You can look through jobs located in your Province; by specific department like the Atomic Energy of Canada or Canada Revenue Agency departments; and even by Municipalities, which can range from small towns to large cities.
Japan is the birthplace of Godzilla, a giant fictional monster created by atomic radiation.
The HEPA filter was created in response to the atomic bomb as a way to filter out harmful radioactive particles.
He states, "In both processes, a small diamond seed is placed in an environment that contains carbon, the atomic component diamond.
Tungsten aka wolfram is a heavy element with an atomic number of 74 and has the highest melting point of all elements.
Joe Rocket Atomic Shoes could be just what you're looking for if you ride a street bike and want cutting edge shoes to go with it.
Even the Joe Rocket website doesn't have the Atomic Shoes-just a fairly large variety of boots.
If you buy a pair of Joe Rocket Atomic Shoes and find yourself a new fan of the brand, there's a whole lot more out there for you.
Slightly challenging to find, but made with the wearer's comfort and durability in mind, the Atomic shoes are worth checking out.
If the Atomic shoes aren't what you had in mind, don't forget to check out some of the other Joe Rocket boots.
Casio Men's Waveceptor Atomic Solar Watch is among the best that Casio has to offer.
Utilizing nifty atomic technology, this timepiece will make you the coolest kid in school...or the office.
Continuing their great run with their G-Shock collection, Casio offers their Men's G-Shock Atomic Tough Solar Watch, complete with solar-powered action.
For the most precise timepieces, look for Waveceptor watches with Atomic timekeeping, which automatically adjusts the watch to keep it accurate.
Look for Waveceptor watches that boast Atomic timekeeping, which automatically adjusts the watch to ensure accurate time using radio signals.
A relatively new development is the atomic watch, which uses radio signals to synchronize the watch with an atomic clock kept elsewhere to ensure accuracy.
If you are looking for the ultimate time keeping device to wake you up in the morning, consider an atomic dual alarm clock radio.
An atomic alarm clock is particularly useful as it means that you need never worry about over sleeping, or getting up in the middle of the night because the alarm clock is telling the wrong time.
An atomic dual alarm clock radio is particularly useful as many people find it easier to wake up to radio than to a buzzing alarm.
Many people find that traveling with an atomic dual alarm clock radio is beneficial as the clock resets itself automatically to any time zone in the United States that you find yourself in.
When buying an atomic alarm clock as a gift then it is an extra special gesture to also buy the batteries to go with it so someone can start using it straight away.
Atomic alarm clocks - like many other types of watches and clocks - sometimes offer a range of features that are not useful to everyone.
Narrowing down the features required will also help to limit the number of atomic alarm clocks to choose from and this can save time when shopping.
An atomic alarm clock, with the ability to synchronize with the official clock, combined with a radio alarm is a sure way to ensure a good start to every day!
The original versions would all have been key wound alarm clocks and while they might not have the time keeping accuracy of an atomic alarm clock or the features of a novelty or cool alarm clock, the design remains highly desirable.
Even the loudest alarm clock or a cool alarm clock is useless if it tells the wrong time, although atomic alarm clocks often change the time automatically.
So is having a clock that automatically updates itself, such as an atomic alarm clock, as this will be useful for traveling between time zones.
Notable Citizen watch lines include the Eco-Drive solar powered watches and the Skyhawk A-T atomic timekeeping watches.
Atomic watches for men are the perfect choice for men who need a reliable time keeping device.
Atomic watches are known world wide for their accuracy.
This type of watch takes the time from the U.S. Government atomic clock.
The atomic clock will not gain or lose any time.
The signal from the atomic clock feeds the National Institute of Standards and Technology (NIST) and this transmits the time signal which is picked up by atomic watches.
Atomic clocks and watches automatically change when the clocks change in the spring and autumn, so this helps to reduce the problem caused by forgetting to alter the time.
Many atomic watches feature a range of different functions as well as a simple time keeping device.
Some atomic watches have a range of features which make them an ideal choice for sports people or people who like outdoor adventure sports.
Atomic watches rely on a signal in order to be able to display the time.
It is useful for an atomic watch to have a quartz movement as back up so that the watch can still be used even if the atomic signal cannot be picked up.
Some atomic watches won't pick up the atomic signal outside of the U.S., therefore an additional quartz movement is essential for travelers.
Many of the main watch manufacturers offer an atomic watch.
Casio Men's Waveceptor Atomic Sport Watch - this watch model features a range of options including a choice of watch strap.
Casio Men's G-Shock Multi-Band Solar Atomic Analog Watch - this watch is waterproof to 660 feet, making it a great choice for someone who enjoys water sports.
The atomic feature means that it gives perfect time in 28 time zones.
E. Howard EH-23GA Gold Atomic Watch - this is a traditionally styled watch which also features a digital display.
Atomic watches for men are an ideal watch for someone who needs accurate time keeping functionality.
The wide range of additional features and functions means that atomic watches can make a great gift for men with a wide variety of interests.
The atomic clock radio revolution allows consumers to set it and forget it, and never miss another important engagement.
Radio-controlled clock, resonance clock, spectroscopy clock and radio clock are all terms that people use to describe an atomic clock.