VELOCITY OF REACTIONS 



reasons are brought forward in favour of a view 

 which Faraday had first expressed, to explain 

 the conducting of electric currents. The molecules 

 of electrolytes are split, to a greater or less extent, 

 into smaller particles which are called Ions. 

 These ions carry the electricity from one pole to 

 the other. They may be considered, as physicists 

 believe, to be compounded of atoms and a certain 

 quantity of electricity. The number of molecules 

 split into ions depends upon the degree of dilution 

 and the temperature. Strong acids and alkalis 

 are practically entirely split up into ions when 

 they are diluted down to o-ooi of one gramm 

 molecule in one litre of water. 



The reactions which such substances undergo 

 may be considered as reactions between ions. 

 We generally call them Ionic Reactions. We shall 

 bear in mind that ionic reactions are carried out 

 with infinitely great velocity. The quantity of 

 ions contained in a solution can be calculated 

 by determining its power of conducting electric 

 currents. The less resistance is offered the more 

 ions are present. The sap of living tissues always 

 contains different ions. Therefore ionic reactions 

 must always take place in living protoplasm. 



Ionic reactions in living cells did not fail to 

 attract much attention amongst biologists. We 

 possess a series of excellent methods for deter- 

 mining the concentration of ions contained in 

 living cells. Some of them permit us to work with 



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