Question

Which of the following compounds will form the precipitate with aq. AgNO₃ solution most readily?

• A.

  

• B.

  

• C.

  

• D.

  

Answer 1

The correct option is B

Explanation for correct option: B
$\mathrm{R}-\mathrm{X}\left(\mathrm{aq}\right)+{\mathrm{AgNO}}_3\left(\mathrm{aq}\right)\to {\mathrm{R}}^{+}\left(\mathrm{aq}\right)+\mathrm{AgX}\left(\mathrm{s}\right)$

1. This means that the rate of formation of precipitate is directly proportional to the formation of carbocation.
2. Now, if we see the formation of carbocation for all the molecules that will be as follows.
3. 
4. The most stable carbocation formed is the second one. All other are primary carbocations.
5. The second carbocation is stable due to back bonding.
6. 
7. Hence, option B is the correct answer.