u. 



m 



Laws of Molecular Force. 13 

 Table IX. — Compounds of Sodium {continued). 



Na 2 O0 4 . Na 2 Cr 2 7 . Na 2 B 4 7 . Na 2 W0 4 . Na P 2 6 . Na 4 P 2 7 . 



.... 186 14-8 17-8 19-7 17-3 24'7 



,o 2-90 237 5-50 2-48 2-53 



(MH)i ... 11-2 15-9 16-5 12-5 15-8 23-2 



M/p 52 91 85 57 82 105 



Other Compounds. 



LiCl. Li 2 C0 3 . AgOl. AgBr. 



• m 12-1 (9 0) 15-5 19-0 (30-3) 173 



p 2-00 ... 241 5-55 ... 642 



(M 2 /)2 4-3 (3-7) 7-4 6-3 (8-0) 6-7 



M/p 21-2 ... 351 25-8 ... 293 



OaCl 2 . SrCl 2 . Ea01 2 . 



•» S-S (141) (15-3) (21-4) 



p 2 22 ... 296) 3-85 



(M 2 0* 9-8 (9-5) (10-6) (12-4) 



M/p 50-5 ... 53-5 54-1 



The first point to attend to in these numbers is to ascertain 

 whether the additive principle applies to the values of (M 2 Z)*. 

 The differences for K and Na are 1*2 in the chlorides, *9 in the 

 bromides, 1/2 in the nitrates, 1*1 in the nitrites, 1*1 in the 

 chlorates, 1*1 in the cyanides, of which the mean is 1*1, This 

 is encouraging enough if we remember the roughnesses of 

 calculation and experiment. Proceeding to take the differ- 

 ences for the compounds of the dibasic acids, we get for 

 K 2 — Na 2 1*9 in the carbonates, 1/8 in the sulphates, 1*4 in the 

 chromates, 1*9 in the bichromates, and 1*6 in the metaphos- 

 phates, the mean of which is 1*72, which is less than twice the 

 mean 1*1 for K — Na. It will be shown later that in a com- 

 pound RS ra , where for instance R represents an n-basic acid 

 and S a monad metal, (M 2 /)*= (F r + wF,)/w*, where F r and F s 

 are the parts due to R and S : according to this principle the 

 value of K 2 — Na 2 in the above compounds ought to be only 

 2i or 1*41 times the value for K + Na! ; while according to 

 the mean values found above, K 2 — Na 2 is 1*6 times K— Na. 

 In view of the relation for RS M , 



(M.H)i/ni = F r /n + F s , 



the best plan is to take values of (M. 2 l)i/ni which are the sums 

 of FJn and F # or the sum of parts not due to atoms but to 



