442 Voltaic Energy of dissolved Chemical Compounds. [Mar. 14, 



chemical changes produced by light in aqueous solutions. The degree 

 of freedom of an aqueous solution of chlorine from hydrochloric acid 

 and of iodine from hydriodic acid was determined much more readily 

 by means of the " voltaic balance " method than by ordinary chemical 

 analysis. 



III. " Relative Amounts of Voltaic Energy of dissolved Chemical 

 Compounds." By G. GORE, F.R.S. Received January 16, 

 1889. 



(Abstract.) 



In this investigation the author has measured, by means of the 

 " voltaic balance," the amounts of relative voltaic energy or of 

 chemical affinity for zinc, of nearly 250 aqueous solutions of dissolved 

 chemical compounds, at ordinary atmospheric temperatures. The sub- 

 stances include compounds of elements with elements ; elements with 

 monobasic, bibasic, and tribasic acids ; acids of all these classes with 

 each other ; elements with monobasic, bibasic, tribasic, and tetrabasic 

 salts ; monobasic, bibasic, and tribasic acids with all these classes of 

 salts ; and all these classes of salts with each other in great variety. 

 The method employed hns been already described (see * Roy. Soc. 

 Proc.,' vol. 44, pp. 181, 294), and he offers the results thus obtained 

 as additional evidence in support of the conclusion, that " every elec- 

 trolytic substance or mixture when dissolved in water unites chemically 

 in definite proportions by weight with every other such dissolved body, 

 provided no separation of substance occurs ;" and that " there may 

 probably be discovered thousands of such compounds, which only 

 exist whilst in aqueous solution, and are decomposed on evaporating 1 

 or crystallising their solutions." The present research has shown the 

 existence of nearly 250. 



The formulae of the compounds, together with the amounts of 

 energy, are arranged in the form of a table as a volta tension series of 

 electrolytes, commencing with I + 01, which gives a plus number of 

 + 11,686,507, and ending with 2(H 3 N + KHO) + (K 2 C0 3 + Na 2 S0 3 ), 

 which gives a minus one of 959,817. The whole of ihe formulas 

 agree with the ordinary chemical equivalents of the substances. 



