Question

Ethyl bromide and isopropyl chloride can be distinguished by:
A. alcoholic $AgN{{O}_{3}}$
B. Comparing their colours
C. Burning the compounds on spatula
D. aqueous $KOH$ solution

Answer 1

Hint: Ethyl bromide and isopropyl chloride are referred to as halogenoalkanes. You should know which test is generally used to identify the presence of what type of halogen is present in a suspected halogenoalkane.


Complete step by step solution:
As per the given question, we should know that ethyl bromide and isopropyl chloride comes under the halogenoalkane family.
And, generally silver nitrate test is performed to detect any halide present in the solution where the halogenoalkanes are treated with silver nitrate solution. On treatment, the reaction produces a significant coloured precipitate by which we can distinguish what halogen is present in the compound.
Here, ethyl bromide and isopropyl chloride are halogenoalkanes but they have two different halogen atoms.
So, they can be distinguished by performing a silver nitrate test.
Where, in addition to silver nitrate with chemical formula $AgN{{O}_{3}}$in ethyl chloride, the reaction will provide a white precipitate which will be soluble in solution.
${{C}_{2}}{{H}_{5}}Cl+AgN{{O}_{3}}\to AgCl\xrightarrow{N{{H}_{4}}OH}SOLUBLE$
 White precipitate
While, in addition to silver nitrate in isopropyl chloride, the reaction will provide a yellow precipitate and the product formed will be insoluble with solution.
${{C}_{2}}{{H}_{5}}Br+AgN{{O}_{3}}\to AgBr\xrightarrow{N{{H}_{4}}OH}INSOLUBLE$
Yellow precipitate
Thus, we can see that two compounds are giving different colours of precipitate and when treated with $N{{H}_{4}}OH$solution they are showing different properties.
Thus, silver nitrate test is widely used for testing the presence of any halogen.

Hence, the correct option is A.


Note: Most probably you may be confused with option B. But, after treating with silver nitrate the compound is giving different coloured precipitate. Thus, the exact option should be A. Halide ions in a solution are usually detected using silver nitrate solutions. The test solution is acidified using a few drops of dilute nitric acid, and then a few drops of silver nitrate solution is added. Then, different coloured silver halide precipitates are formed where depending on the halide ions present different colours are formed. For example, chloride ions give a white precipitate, bromide ions give yellow precipitate, etc.