Which of the following give ether ?

Options

A. `CH_(3)CH_(2)O Na` and `C_(2)H_(5)I`
B. `CH_(3)-CH_(2)-OHunderset(140^(@)C)overset(H^(o+))(to)`
C. `CH_(3)-CH_(2)-Ioverset("dry"Ag_(2)O)(to)`
D. All of the above

Answer

To determine which of the following reactions give ether, we will analyze each reaction step by step.

### Step 1: Reaction with Sodium Ethoxide and Alkyl Halide
1. **Identify the reactants**: Sodium ethoxide (CH3CH2O^-Na^+) and ethyl iodide (CH3CH2I).
2. **Mechanism**: This reaction follows the SN2 mechanism.
3. **Nucleophilic attack**: The ethoxide ion (CH3CH2O^-) attacks the electrophilic carbon in ethyl iodide (CH3CH2I), resulting in the formation of diethyl ether (CH3CH2OCH2CH3) and sodium iodide (NaI).
4. **Product**: The product formed is diethyl ether.

### Step 2: Reaction of Alcohol in Acidic Medium
1. **Identify the reactants**: Ethanol (CH3CH2OH) and H^+ (acid).
2. **Protonation**: The alcohol is protonated to form protonated ethanol (CH3CH2OH2^+).
3. **Mechanism**: This reaction also follows the SN2 mechanism.
4. **Nucleophilic attack**: Another molecule of ethanol acts as a nucleophile and attacks the protonated ethanol, leading to the formation of diethyl ether (CH3CH2OCH2CH3) and water.
5. **Product**: The product formed is diethyl ether.

### Step 3: Reaction with Dry Silver Oxide
1. **Identify the reactants**: Ethyl iodide (CH3CH2I) and dry silver oxide (Ag2O).
2. **Mechanism**: On heating, the silver oxide facilitates the elimination of iodine and formation of ether.
3. **Nucleophilic attack**: The ethyl group reacts with another ethyl iodide to form diethyl ether (CH3CH2OCH2CH3) and silver iodide (AgI).
4. **Product**: The product formed is diethyl ether.

### Conclusion
After analyzing all three reactions, we find that all of them produce ether. Therefore, the answer is that all of the above reactions give ether.

### Final Answer
**All of the above reactions give ether.**

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