The atomic weight of ruthenium was determined by A.
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.
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.
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.
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.
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.
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.
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.
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.
Among other researches relating to atomic and molecular magnetism are those of 0.