254 On the Electrolysis of Secondary Compounds. 



of substances of iso-electric powers. Of such electrolytes it 

 may be convenient to distinguish the following classes: — 



1st. An electrolyte may consist of simple ions, and then 

 must be constituted of a single equivalent of a metal (or H) 

 for its cation, and a single equivalent of a non-metallic ele- 

 ment for its anion ; as K, I ; Ag, CI ; &c. ; they may be termed 

 simple electrolytes. 



2nd. An electrolyte may consist of a compound cation, a 

 single equivalent of which must take the place of a metal ; and 

 a single equivalent of a simple non-metallic anion, as Nri4, CI. 

 Organic alkalies probably form compound cations of this na- 

 ture, and when their salts are electrolysed, hydrogen is always 

 disengaged with them at the platinode, as with ammonia; 

 these and the following we may call complex electrolytes. 



3rd, An electrolyte may consist of a compound anion, a 

 single equivalent of which would take the place of the simple 

 non-metallic anion, with a single equivalent of a simple cation, 

 a metal (or H), as H, NC^; K, SO4; Na, NOg. 



4-th. An electrolyte may consist of a single equivalent of a 

 compound cation, and a single equivalent of a compound anion, 

 as NH4, SO4. 



These four cases may be included in the term Monobasic 

 Electrolytes, as a single equivalent of force (measured by the 

 voltameter) would electrolyse single equivalents of the elec- 

 trolytes. 



5th. An electrolyte may also consist of tiao or more equiva- 

 lents of a metallic cation or (H), or oi single equivalents (jf't'wo 

 or more metallic cations (or H) ; when the anion must consist 

 of a single equivalent of a compound ion, as (Kg FeCyy). This 

 compound ion, in the case of an oxysalt, contains the so-called 

 anhydrous acid in combination with as many equivalents of 

 oxygen as there are of metallic cations (or H) in the com- 

 pounds, as (Nag, PgOg, O3). 



In this case as many equivalents of force will be required 

 for the electrolysis of one equivalent of the electrolyte as there 

 are equivalents of metal (or H) in the cation. They may be 

 denominated Polyhasic Electrolytes. 



In these compound anions and cations, it would appear that 

 the oxygen which travels with the acid group, and the hy- 

 drogen which is evolved with the alkaline group, must be con- 

 nected with the other elements whilst under the influence of 

 the current in a manner differing from that in which the latter 

 are combined together: for we have found that in most cases 

 this connection is immediately dissolved upon their escape 

 from the electric influence, whilst in some others their appa- 

 rent permanent combination is only the effect of secondary 



