Avogadro and Dalton: the standing in chemistry of their hypotheses / by Andrew N. Meldrum, D.SC ; with a preface by Francis R. Japp.

  • Meldrum, Andrew Norman, 1876-1934.
Date:
1904
Catalogue details

Licence: In copyright

Credit: Avogadro and Dalton: the standing in chemistry of their hypotheses / by Andrew N. Meldrum, D.SC ; with a preface by Francis R. Japp. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    42/124 (page 38)
    Admitting that this conjecture is possibly right, one may go on to enquire why the same line of argument should be taken only in the case of argon and its congeners. It is easy enough to take it further. No atomic weight method is final. The mercury molecule may consist of atoms which are gifted with a very high degree of mutual affinity, and it may well be so stable that no internal work is done on heating it—so stable, indeed, that no chemical agent is able to sepa- rate the atoms. The carbon atom may consist of smaller atoms gifted with a very high degree of mutual affinity, so that the atomic weight of carbon is a fraction of 12. Speculation may be continued without end on these lines. The smaller atoms which make up what we know as the carbon atom may not be all of the same kind, so that carbon is not an element. The truth is, that if Armstrong's argument be allowed, all atomic weights are uncertain. If his method be adopted, the atomic weights, one and all, are anything you please. The recognised antidote to speculation is experiment. Armstrong's criticism, being purely speculative, does not even touch the empirical proof of the Cp / Cv method. With monatomic mercury the ratio got is r66, with polyatomic molecules 141 or less. Until a molecule known to be poly- atomic is found to give the ratio or higher, the empirical proof remains untouched.