Hello, I have to choose a method to determine Ag +% in groundwater (Morh, Volhard or Fanjas). I don't have to do calculations.

The thing is, I don't know how to start, should I assume that the groundwater has Ag +?

In the exercises, I only solve problems to determine the Cl-% or [Cl-] but never with Ag + and in the books I found the 3 methods, but I always use them to determine Cl-

Could someone help me with this? I think I have to choose Volhard's Direct Method, but I'm not sure. Sorry if this is a dumb question.