488 On the Molecular Constitution of Water. 



their elaborate examination of the delicate nuances in the 

 physical properties of watery mixtures, that the alcohols, sul- 

 phuric acid, amines, and other compounds combine molecularly 

 with water to form such bodies as (J 2 H 6 0-f-12H 2 0, 3C 2 H 6 

 + H 2 0, H 2 S0 4 + H 2 0, H2SO4 + 6H2O, and the like. These 

 must be further examples of the tendency to polymerization 

 due to the tetrad or higher valency of oxygen. In water of 

 crystallization the same principle is at work. The methods 

 of this paper can be applied to other associating liquids. 



9. Summary of Results. 



Ordinary water-vapour being H 2 0, which it is proposed to 

 call internationally hydrol, ice is trihydrol (H 2 0) 3 , and water 

 a mixture of trihydrol and dihydrol (H 2 0) 2 , the proportions 

 of which tire determined by equations (7) and (9) up to 100° 

 and approximately to 200°. Probably at its critical tempera- 

 ture water is practically pure dihydrol. The latent heat of 

 fusion of ice is not an ordinary physical latent heat of fusion, 

 but is mostly a latent heat of dissociation of trihydrol into 

 dihydrol, partly masked by heat of solution of trihydrol in 



Table XIII. 





Density p 

 at0°. 



Temp.-coeff.ot 

 density, k. 



w 2 -l 1 i 



2 i o • ~ Compressibility 



at 0° P er a(;m0 at 0°- 



Dibydrol ... 

 Trihydrol ... 



1-08942 

 ■88 



•0009 

 •0002 



•20434 -000016 



•20968 000010 ? 



I 





Surface- 

 tension at 0°. 



Critical Specific heat 

 temperature. at 0°. 



Virial 

 Constant. 



Dihydrol ... 

 Trihydrol ... 



78 - 3 

 7332 



368 O. -8 

 538 C. -6 



16200 x10 s 

 ] 5400 x10 s 





Latent heat 

 of fusion. 



Latent heat 



of evaporation 



at 100°. 



Viscosity at 

 0°. 



Pressure-coeff. 

 of viscosity 

 per atmo. 



Dihydrol ... 

 Trihydrol ... 



16 cal. 



257 cal. 

 250 (near) 



•0030 

 •0381 



•00034 



_J 



2H 2 0=(H 2 0) 2 +189x2xl8 cal. 



3(H 2 0) 2 =2(H 2 0) 3 4-177 x6 X 18 cal. 



