why is ferric chloride preferred over potassium chloride in case of a cut leading to bleeding?
Ferric chloride results in faster coagulation of blood around the wound , stopping further bleeding. coagulating power of an electrolyte is proportional to its valenc. since vanlency of Fe+3 is higher compared to K+ as in case of KCl , K+ is only mono-valent ion hence, less effective .
Moreover, FeCl3 does not lead to irritation while KCl may lead to severe irritation round the wound.
According To hardy schulze rule the coagulating capacity of different electrolytes depend upon the valency of the active ion, higher is the valency higher will be its coagulating power.
For the same reason , FeCl3which releases Fe3+have higher coagulating power than K+ion therefore FeCl3will act efficiently than KCl.