Which of the following amines give mustard oil smell with `HgCl_(2)+CS_(2)`?
(I) Aniline
(II) Diethyl amine
(III) P - toluidine
(III) P - toluidine
(IV) N, N - Diethyl propanamine

Options

A. (I) & (II)
B. (II) & (IV)
C. (II) & (III)
D. (I) & (III)

Answer

To determine which of the given amines give a mustard oil smell when reacted with HgCl₂ and CS₂, we need to analyze the structure of each amine and identify their classification (primary, secondary, or tertiary). The mustard oil test is specific to primary amines.

### Step-by-Step Solution:

1. **Identify the Amines:**
- (I) Aniline: C₆H₅NH₂ (Primary amine)
- (II) Diethyl amine: (C₂H₅)₂NH (Secondary amine)
- (III) P-toluidine: C₆H₄(CH₃)NH₂ (Primary amine)
- (IV) N,N-Diethylpropanamine: C₂H₅NH(C₂H₅)C₃H₇ (Tertiary amine)

2. **Classify Each Amine:**
- Aniline is a primary amine.
- Diethyl amine is a secondary amine.
- P-toluidine is a primary amine.
- N,N-Diethylpropanamine is a tertiary amine.

3. **Apply the Mustard Oil Test:**
- The mustard oil test is positive for primary amines. When primary amines react with HgCl₂ and CS₂, they produce thiourea derivatives that have a characteristic mustard oil smell.
- Secondary and tertiary amines do not react in this manner and therefore do not produce the mustard oil smell.

4. **Conclusion:**
- From the classification:
- Aniline (Primary) - **Gives mustard oil smell**
- Diethyl amine (Secondary) - **Does not give mustard oil smell**
- P-toluidine (Primary) - **Gives mustard oil smell**
- N,N-Diethylpropanamine (Tertiary) - **Does not give mustard oil smell**

5. **Final Answer:**
- The amines that give a mustard oil smell with HgCl₂ and CS₂ are **Aniline and P-toluidine**.