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: Iodine is poorly soluble in water ( 0.001M). Therefore, to obtain useful solutions as an analytical reagent it is dissolved in:
Options: <0> 0.1 M potassium nitrate <1> Perchloric acid 0.01 M. <2> Excess of calcium nitrate. <3> Potassium iodide. <4> Hot water.
A:
chemistry