The ratio of the specific heats of air and of carbon dioxide

Abstract

Although our knowledge of the energy-content of solid bodies has been greatly extended by the theoretical investigations of Planck, Einstein and Debye, and by the experiments of Dewar, Nernst and others, the problem in the cases of gases, and especially of vapours, is still far from a satisfactory solution. With the object of providing accurate data for a theoretical study of the energy-content of molecules in gases, the experiments described in this paper were commenced in 1911 in the laboratory of the Physikalisch-Chemisches Institut of the University of Berlin. I desire to express my thanks to Prof. Nernst for the interest he showed in this work, and for many useful suggestions he made during the period 1911-1913, in which I worked in his laboratory. Since air and carbon dioxide have been the object of some very careful investigations by previous experimenters, it was decided that a re-investigation of the ratio of the specific heats, c p / c v , of these gases would be appropriate at the commencement of the research. Other gases, for which the constants are less accurately known, such as ammonia, sulphur dioxide, nitrous oxide and nitrogen, are at present under investigation by a method similar to that described in the present communication. The present results were published in an abstracted form in 1913.