350 EXPERIMENTS ON DIFFUSION IN RELATION TO THE KINETIC THEORY OF GASES. 



If, however, for our immediate purpose, we assume the smallest molecular 

 volume of oxygen given by Kopp as derived from a comparison of the volume 

 of tin with that of its oxide and put 



b(0=16) = 27, 

 we find for the diameters of the molecules 



4 



TABLE IV. 



Hydrogen . . . . 5'8 tenth-metres. 



Oxygen 7-6 



Carbonic Oxide . . 8-3 



Carbonic Acid ... 9-3 



The mass of a molecule of hydrogen on this assumption is 



4'6 x 10"" gramme. 



The number of molecules in a cubic centimetre of any gas at 0"C. and 



760 mm. B. is 



AT= 19x10". 



Hence the side of a cube which, on an average, would contain one molecule 

 would be 



^V"* = 37 tenth-metres. 



