Identify the product `C` in the series
`CH_(3) CN overset (Na//C_(2) H_(5) OH) to A overset (HNO_(2)) to B overset ("Tollens reagent") to C`

Options

A. `CH_(3)COOH`
B. `CH_(3)CH_(2)NHOH`
C. `CH_(3)CONH_(2)`
D. `CH_(3)CHO`

Answer

To solve the problem step by step, we will analyze the transformations that occur in the series of reactions starting from the compound \( CH_3CN \).

### Step 1: Identify the starting compound
The starting compound is \( CH_3CN \), which is acetonitrile.

### Step 2: First reaction with Na/C2H5OH
The first reaction involves treating acetonitrile (\( CH_3CN \)) with sodium (Na) in the presence of ethanol (\( C_2H_5OH \)). This reaction is a reduction process that converts the nitrile group (\(-CN\)) into an amine group (\(-NH_2\)).

**Product A**: The product formed after this reaction is \( CH_3CH_2NH_2 \) (ethylamine).

### Step 3: Second reaction with HNO2
Next, product A (\( CH_3CH_2NH_2 \)) is treated with nitrous acid (\( HNO_2 \)). This reaction leads to the formation of an N-nitroso compound, which can rearrange to form a carbonyl compound.

**Product B**: The product formed after this reaction is \( CH_3CH_2N=O \) (an oxime) which can further rearrange to form an aldehyde or ketone. In this case, it rearranges to form \( CH_3CHO \) (acetaldehyde).

### Step 4: Third reaction with Tollens' reagent
The final step involves treating product B (\( CH_3CHO \)) with Tollens' reagent. Tollens' reagent is used to oxidize aldehydes to carboxylic acids.

**Product C**: The product formed after this reaction is \( CH_3COOH \) (acetic acid).

### Final Answer
Thus, the final product \( C \) in the series is \( CH_3COOH \) (acetic acid).

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