190 Mr. M. M. Pattison Muir 



on 



Table III. 



A. B. *. 



Hydrochloric acid. Metallic chloride. 1 



Sulphuric acid. Metallic sulphate. 0*5 



The metal may be magnesium, iron, manganese, nickel, 

 cobalt, or copper. 



Table IV. 



A. B. h. 



R"C1. J(W S0 4 ). 1 



R'"C1, i(Bs w S0 4 ). 2 



R" = metal of Table II. R'" = metal of Table III. 



2. Systems consisting of two Insoluble and tivo Soluble 

 Substances. 



In the case of insoluble compounds the active mass of the 

 substance does not necessarily decrease in the same proportion 

 as the total mass of the substance present. Increase of the 

 absolute amount of an insoluble substance does not increase the 

 active mass of that substance to any sensible extent. Thus, 

 1 grm. of an insoluble salt in 100 cub. centims. of liquid pro- 

 duced the same effect as 2 grms. of the salt. 



Supposing, then, that the masses of the insoluble substances 

 are constant during the experiments, these masses enter the 

 equations as unknown constant quantities, the value of which 

 may be determined from the experimental data, either indepen- 

 dently or along with other unknown constants. Under these 

 conditions, the proportion between the amounts of the two so- 

 luble substances is always the same when the system is in equi- 

 librium. 



The value of jf is determined for the systems now under consi- 

 deration by aid of the formula 



*~ 1 + Cl ' W 



where 



«=* 



(p 1 and qi = masses of A x and B 2 , the soluble substances pre- 

 sent). If the element of time be introduced, equation (4) 

 becomes 



Iognai(^>*^^U ... (5) 

 ,?; = amount of substance A 1 transformed into Bj in time t. 



