Detailed Instructions: In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.
Q: Question: A potentiometric titration is always done at i = 0:
Options: <0> Yes, because that is where the Nernst equation is fulfilled. <1> Yes, because it is an instrumental requirement. <2> No, because there are potentiometric titrations at constant i. <3> No, because potentiometric titrations are never made at i = 0. <4> Yes, as long as an indicator electrode and a reference electrode are used.
A:
chemistry