312 



Mr. J. Frenkel on the Surface Electric 



Taking the experimental values of the surface-tension of 

 fused metals *, I have calculated, by means of (14) and (12), 

 their atomic radii (r N >, and further, by means of (8), the 

 corresponding intrinsic potentials (V). The results are 

 collected in the following Table (III.)- The numbers (*), 

 tabulated in the second column, do not, strictly speaking, 

 represent the valency, but the probable number of external 

 electrons, determined by the position of the corresponding 

 metal in the periodic system. As a matter of fact, this 

 number may be different. For instance, copper, silver, and 

 gold are included in the first group, although copper is often 

 di-valent, and gold tri-valent. It is possible that for silver 

 k is also larger than 1. 



Table III.— Su] 



'face-tension and intrinsic 



potentials. 



i. 



Element. 



II. 



Valency 



K. 



III. 



Atomic 



weight 



A. 



IV. 



Specific 

 weight 



V. 



Surface- 

 tension 



cm. 



(observed). 



VI. 



Atomic 



radius 



(calcul.) 



rXlO 8 cm. 



VII. 



Intrinsic 

 potential 

 (calcul.) 

 V volts. 



VIII. 



Intrinsic 



potential 



(observed) 



volts. 



Na 



K 



Ag 



Zn 



Cd 



Hg 



Sn 



Pb 



Sb 



Bi 



Fe 



Pt 



1 

 1 

 1 

 2 

 2 

 2 

 4 

 4 

 5 

 5 

 8 

 8 



23 



39 

 108 



65 

 112 

 201 

 119 

 207 

 120 

 208 



56 

 195 



093 

 0-83 

 951 

 6-48 

 8 



13-6 

 6-94 



10-64 

 65 



100 

 6-88 



21-3 



294 

 415 

 784 

 104 (?) 

 815 (?) 

 436 

 681 

 536 

 317 

 460 

 950 

 1820 



2-4 



2-58 



1-97 



0-58 



1-43 



1-36 



099 



0-99 



0-68 



0-83 



0-42 



0-57 



4-2 



2-55 



623 



1-24 



5-42 



4-00 



4-21 



3-66 



230 



3-11 



318 



510 



1*81 

 51 



Let us first consider the calculated values of the intrinsic 

 potentials (column VII.). The main fact about them is that 

 they are all of the right order of magnitude and lie in very 

 narroio limits, in spite of the considerable variation of k. 

 The only metal for which the direct comparison of the 



* Landolt-Bornstein, Physikalisch-Chemische Tabellen for 1911, p. 114. 

 It must be remarked that the discrepancy between the values of a found 

 by different persons does not affect the order of magnitude. 



