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: Reactions in which there are no intermediates are described as: 
 Options:  <0> Concerted. <1> Polar <2> Radicals <3> Homolitic <4> Heterolithic

A: chemistry
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Q: Question: Point out which of the following is more clearly a positive symptom of schizophrenia: 
 Options:  <0> The flat or dull affection. <1> The poverty of language. <2> The associability. <3> Hallucinations <4> The bulimia.

A: psychology
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Q: Question: Potentiometric titration of chloride with a silver electrode, using a silver ion standard solution: 
 Options:  <0> It is based on the formation of silver complexes in the presence of a high concentration of chloride. <1> Follow the Nernst equation, in which the variation of the potential varies linearly with the concentration of silver ion. <2> It shows an equivalence point where pAg does not depend on the chloride concentration. <3> It gives rise to potential variations that depend on the amount of AgCl formed. <4> It provides a titration curve in which the jump of pAg does not depend on the concentration of chloride.

A:
chemistry
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