Match List-I with List-II and select the correct answer using the Codes given below : List-I (Reagent) – List-II (Used as test reagent for) (A) Ammonical $AgNO_{3}$ – (i) Primary amine (B) $HIO_{4}$ – (ii) Aldehyde (C) Alkaline $KMnO_{4}$ – (iii) Vicinal-OH- group (D) Chloroform + NaOH – (iv) Double bond

Q: Match List-I with List-II and select the correct answer using the Codes given below : List-I (Reagent) – List-II (Used as test reagent for) (A) Ammonical $AgNO_{3}$ – (i) Primary amine (B) $HIO_{4}$ – (ii) Aldehyde (C) Alkaline $KMnO_{4}$ – (iii) Vicinal-OH- group (D) Chloroform + NaOH – (iv) Double bond

Match List-I with List-II and select the correct answer using the Codes given below : List-I (Reagent) – List-II (Used as test reagent for) (A) Ammonical $AgNO_{3}$ – (i) Primary amine (B) $HIO_{4}$ – (ii) Aldehyde (C) Alkaline $KMnO_{4}$ – (iii) Vicinal-OH- group (D) Chloroform + NaOH – (iv) Double bond

Question

Accepted Answer

To justify why Option 3 is the correct answer, let's examine each reagent in List-I and its corresponding use as a test reagent in List-II:

(A) Ammonical $AgNO_{3}$ – (ii) Aldehyde  
Ammonical silver nitrate, also known as Tollen's reagent, is used to test for aldehydes. Aldehydes reduce the silver ion in Tollen's reagent to metallic silver, forming a silver mirror on the inner surface of the test tube. This reaction is specific to aldehydes and does not occur with ketones, making (A) match with (ii).

(B) $HIO_{4}$ – (iii) Vicinal-OH- group  
Periodic acid ($HIO_{4}$) is used to cleave vicinal diols (vicinal-OH groups) into aldehydes or ketones. This reaction is specific to vicinal diols, where the hydroxyl groups are on adjacent carbon atoms. Therefore, (B) matches with (iii).

(C) Alkaline $KMnO_{4}$ – (iv) Double bond  
Alkaline potassium permanganate is used to test for the presence of double bonds in alkenes. It oxidizes the double bond, resulting in the formation of diols, and the purple color of $KMnO_{4}$ is decolorized. This makes (C) match with (iv).

(D) Chloroform + NaOH – (i) Primary amine  
The combination of chloroform and sodium hydroxide is used in the carbylamine reaction, which is a test for primary amines. When a primary amine is treated with chloroform and an alkali, it forms an isocyanide (carbylamine), which has a very unpleasant odor. Thus, (D) matches with (i).

Now, let's explain why the other options are incorrect:

1. A-ii, B-iii, C-i, D-iv: This option incorrectly matches C with i and D with iv. Alkaline $KMnO_{4}$ is not used for primary amines, and chloroform + NaOH is not used for double bonds.

2. A-iv, B-ii, C-i, D-iii: This option incorrectly matches A with iv, C with i, and D with iii. Ammonical $AgNO_{3}$ is not used for double bonds, alkaline $KMnO_{4}$ is not used for primary amines, and chloroform + NaOH is not used for vicinal-OH groups.

4. A-iv, B-iii, C-ii, D-i: This option incorrectly matches A with iv and C with ii. Ammonical $AgNO_{3}$ is not used for double bonds, and alkaline $KMnO_{4}$ is not used for aldehydes.

In conclusion, Option 3 correctly matches each reagent with its specific test application, making it the correct answer.