g You are given an aqueous solution of a sodium halide salt (NaCl, NaBr, or NaI). You have a solution of silver nitrate and a solution of ammonia available. Describe an experimental procedure to determine which of the three salts is present in the solution. b. Chlorine water (made by bubbling Cl2 (g) through water) is added to a solution of a sodium halide salt. Hexane is then added, and the mixture is gently agitated. The hexane layer turns purple. What is the identity of the salt-- NaCl, NaBr, or NaI

See explanation

Explanation:

If i have a sodium halide salt which can be any of NaCl, NaBr, or NaI, addition of  AgNO3 and ammonia leads to the formation of various colour of precipitate which helps to identify the particular halogen atom that is combined with sodium.

If the sodium halide is NaCl, a white precipitate is formed when AgNO3 is added. The precipitate is soluble in ammonia solution.

If the sodium halide is NaBr, a cream precipitate is formed when AgNO3 is added. This precipitate is sparingly soluble in excess ammonia solution.

If the sodium halide is NaI, a yellow precipitate is formed when AgNO3 is added. This precipitate is insoluble in excess ammonia solution

b) The true color of a halogen is only observed when it is viewed in hexane. iodine in hexane has a purple colour. Hence, the reaction that occured is;

NaI(aq) + Cl2 →  NaCl(aq) + I2

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.