Which of the following is a false statement?

Options

A. The major product of the reaction of ethyl iodide with silver cyanide is ethyl isocyanide
B. The formation of ether from the reaction of methyl iodide with dry `Ag_(2)`O is called Williamson’s synthesis
C. The test of chloroform is possible with Hofmann carbylamine reaction
D. Iodoform gives violet vapours on heating

Answer

To determine which of the statements is false, let's analyze each option step by step:

### Step 1: Analyze Option 1
**Statement:** The major product of the reaction of ethyl iodide with silver cyanide is ethyl isocyanide (CH3CH2NC).

- **Explanation:** Ethyl iodide (C2H5I) reacts with silver cyanide (AgCN). In this reaction, the cyanide ion (CN-) acts as a nucleophile and attacks the ethyl iodide, leading to the formation of ethyl isocyanide (CH3CH2NC) as the major product. The iodide ion (I-) is a good leaving group, facilitating this substitution reaction.
- **Conclusion:** This statement is **true**.

### Step 2: Analyze Option 2
**Statement:** The formation of ether from the reaction of methyl iodide with dry silver oxide is called Williamson's synthesis.

- **Explanation:** Williamson's synthesis involves the nucleophilic substitution of alkyl halides with alkoxides to form ethers. In this case, dry silver oxide (Ag2O) does not provide an alkoxide. Instead, it is typically used to generate alkoxides from alcohols. Therefore, the reaction of methyl iodide with dry silver oxide does not fit the definition of Williamson's synthesis.
- **Conclusion:** This statement is **false**.

### Step 3: Analyze Option 3
**Statement:** The test of chloroform is possible with Hofmann Carbyl Amine Reaction.

- **Explanation:** The Hofmann Carbyl Amine Reaction involves the reaction of primary amines with chloroform (CHCl3) in the presence of a base to produce isocyanides. This reaction indeed requires chloroform, and thus the presence of chloroform is essential for this reaction to occur.
- **Conclusion:** This statement is **true**.

### Step 4: Analyze Option 4
**Statement:** Iodoform gives violet vapors on heating.

- **Explanation:** Iodoform (CHI3) is known to decompose upon heating, producing iodine (I2) gas, which is characterized by violet vapors. This is a well-documented property of iodoform.
- **Conclusion:** This statement is **true**.

### Final Conclusion
The false statement among the options is **Option 2**: "The formation of ether from the reaction of methyl iodide with dry silver oxide is called Williamson's synthesis."

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