160 



PHENOMENA, ATOMS, AND MOLECULES 



TABLE IV 

 "Wd" from Experiments with Nitrogen 



degree of dissociation and the heat of formation of hydrogen molecules. 

 The experiments at low pressures lead to a somewhat detailed knowledge 

 of the mechanism of the reaction taking place in the surface of the wire. 



THE DISSOCIATION OF HYDROGEN INTO ATOMS 



PART TWO 



CALCULATIiDN OF THE DEGREE OF DISSOCIATION AND 

 THE HEAT OF FORMATION 



The first part of this paper ^ dealt with experiments on the heat losses 

 from fine tungsten wires in hydrogen at pressures ranging from o.oio mm. 

 up to atmospheric pressure. The results were given in a series of tables, 

 and form the basis for the present calculation of the degree of dissociation 

 and the heat of formation of molecular hydrogen. 



^ Langmuir and Mackay, Jour. Amer. Chem. Soc, jd, 1708 (1914)- 



