CONTENTS OF PART II 



PAGE 



THE DIVISION OF THE WORK AND THE TREATMENT CHOSEN 9 



PART II. 

 CHEMICAL STATICS. 



CONTENTS AND ARRANGEMENT n 



The atomic hypothesis i r 



The molecular hypothesis 13 



/. MOLECULAR WEIGHT AND POLYMERISM. 



Molecular weight determinations by chemical methods . . 15 



Physical methods for determination of molecular weight . 16 



i. MOLECULAR WEIGHT DETERMINATION IN DILUTE 



GASES - 16 



A. Avogadro's law 16 



B. Methods for molecular weight determination in gases 19 



1. Ordinary process ......... 19 



2. Determination of vapour density by means of the second law 



of thermo-dynamics . . . ... . .20 



C. Results 22 



1. Connexion with the atomistic hypothesis .... 22 



2. Confirmation and testing of atomic weights . . .23 



3. Nature of the elementary molecules, and polymerism . . 24 

 Polyatomicity. Hydrogen ... . . .24 



Monatomic elements. Mercury ...... 25 



Allotropy of the elements. Ozone and oxygen ... 26 

 Dissociation of the elements at high temperature. The 



halogens .......... 26 



Polymerism 27 



