Sackur-Tetrode formula

The above table, from which we have concluded the most probable value of C0 to be —1 62 is thus a verification of the Sackur-Tetrode formula which we may well claim to be unexpectedly striking in view of the difficulty of the experimental test. For mercury in particular, for which by far the most accurate data are available, the agreement is perfect. 

The statistical mechanics formula writes the molar entropy as the sum of a translational contribution and an internal contribution 5m = 5m,trans + 5m,int- The translational contribution is given by the Sackur-Tetrode equation ... 

The Sackur-Tetrode equation was derived independently by Otto Sackur (1880-1914), a German physical chemist, and Hugo Martin Tetrode (1895-1931), a Dutch physicist, in 1912. While it is possible to calculate the absolute entropy of molecules including polyatomic gases with their multiple vibrations, we will only give a brief illustration for diatomic CO gas that uses the energy formulas we have previously derived. Consider = G gas at 298.15°K. First we consider the translational entropy as... 

Theoretical Calculation of the Integration Constant of the Vapour-pressure Formula.—Equation (103) was obtained almost simultaneously by Sackur and by Tetrode f we... 

We shall not deal here with certain criticisms of the above derivation which (in contrast with Sackur s theory) applies no quantum considerations of any sort to the gas itself they are met in part by an analogous but very generalized derivation published by Tetrode in 1915. Stem s argument finds considerable support from its final result, formula (108), which is of extreme interest, and in... 

Experimental Test.—Calculations of a somewhat provisional character to check formula (103) have been already put forward by Sackur loc. cit.) and by Tetrode (loc. cit.) in view of the great importance of the whole question, I have occupied myself, with the assistance of my co-workers, in extending and critically reviewing the available material. 

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