Task: Question Answering
Input (English): Question: Potentiometric titration of chloride with a silver electrode, using a silver ion standard solution: 
 Options:  <1> It is based on the formation of silver complexes in the presence of a high concentration of chloride. <2> Follow the Nernst equation, in which the variation of the potential varies linearly with the concentration of silver ion. <3> It shows an equivalence point where pAg does not depend on the chloride concentration. <4> It gives rise to potential variations that depend on the amount of AgCl formed. <5> It provides a titration curve in which the jump of pAg does not depend on the concentration of chloride.
Output (English): 3