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Identifying An Unknown Liquid And Precipitate

A high-boiling bp = 202 - 204 degrees C, burns with a yellow, sooty flame. Sodium fusion indicates that halogens, nitrogen and sulfur are not present. It is not soluble in water, dilute sodium bicarbonate solution, or dilute hydrochloric acid. However, it proved to be soluble in 5% aqueous sodium hydroxide solution. The compound gives a purple color with ferric chloride solution and precipitate when reacted with bromine-water. Treatment with hydroxylamine reagent did not give a reaction, but a white precipitate was obtained when the compound was treated with alpha-napthyl isocyanate. On drying, this white, solid derivative had a melting point of 127 - 129 degrees C.

Identify the original liquid and write a structure for the solid derivative. After identifying the unknown liquid can you indicate what the structure of the precipitate obtained on reaction with bromine might be?

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Yellow sooty flame indicates little oxygen and fairly high organic content-Many liquids burn with a characteristic flame. An aromatic hydrocarbon burns with a yellow, sooty flame. Aliphatic hydrocarbons burn with yellow flame but much less sooty. As the oxygen content increases the flame becomes more and more blue. Think of methanol flames which are ...

Solution Summary

This solution is comprised of a step by step explanation of how to identify a liquid and its precipitate based on chemical properties such as color of the flame, solubility, and treatment with hydroxylamine reagent.