`C_(2)H_(5)OH` and `CH_(3)COOR` can be separated from `CH_(3)CHO` using

Options

A. Tollen's reagent
B. `I_(2)//NaOH`
C. `NH_(2)NH_(2)`
D. `NaHSO_(3)`

Explanation

To solve the problem of separating `C2H5OH` (ethyl alcohol) and `CH3COOR` (an ester) from `CH3CHO` (acetaldehyde), we can use a specific reagent that selectively reacts with one of the compounds while leaving the others unaffected.

### Step-by-Step Solution:

1. **Identify the Compounds**:
- We have three compounds: Ethanol (`C2H5OH`), an ester (`CH3COOR`), and acetaldehyde (`CH3CHO`).

2. **Choose a Suitable Reagent**:
- The Tollens' reagent (which contains silver nitrate in ammonia) is a good choice here. It selectively reacts with aldehydes, such as acetaldehyde (`CH3CHO`), but does not react with alcohols or esters.

3. **Reaction with Tollens' Reagent**:
- When we add Tollens' reagent to the mixture, it will react with acetaldehyde to form a silver mirror (indicating the presence of the aldehyde). Ethanol and the ester will remain unchanged.

4. **Separation Process**:
- After the reaction, we can separate the silver mirror (which indicates the presence of acetaldehyde) from the remaining solution that contains ethanol and the ester.

5. **Final Separation**:
- Since ethanol and the ester do not react with Tollens' reagent, they can be separated from the aldehyde. To further separate ethanol from the ester, we can use a method such as fractional distillation, as they have different boiling points.

### Conclusion:
By using Tollens' reagent, we can effectively separate acetaldehyde from ethanol and the ester.