Identify the product C in the series
`CH_(3)CN overset("Na/"C_(2)H_(5)OH)(rarr) A overset(HNO_(2))(rarr) B overset("HolCu/573K")(rarr) `C

Options

A. `CH_(3)`COOH
B. `CH_(3)CH_(2)`NHOH
C. `CH_(3)"CONH"_(2)`
D. `CH_(3)`CHO

Explanation

To solve the problem, we will analyze the reaction sequence step-by-step:

### Step 1: Formation of Product A
- Starting compound: **CH₃CN** (propanenitrile)
- Reagent: **Na/C₂H₅OH** (sodium in ethyl alcohol)

In this step, sodium acts as a reducing agent and reduces the nitrile (–CN) group to a primary amine. The reaction converts the nitrile to an amine:
- **CH₃CN** → **CH₃CH₂NH₂** (Product A)

### Step 2: Formation of Product B
- Starting compound: **CH₃CH₂NH₂** (Product A)
- Reagent: **HNO₂** (nitrous acid)

When a primary amine reacts with nitrous acid, it forms a diazonium salt which decomposes to produce an alcohol and nitrogen gas. The reaction can be summarized as follows:
- **CH₃CH₂NH₂** + **HNO₂** → **CH₃CH₂OH** (Product B) + **N₂** (gas)

### Step 3: Formation of Product C
- Starting compound: **CH₃CH₂OH** (Product B)
- Reagent: **Cu/HOT, 573K** (hot copper at 573 K)

In this step, the primary alcohol is oxidized to an aldehyde when treated with hot copper. The oxidation of the alcohol results in the formation of:
- **CH₃CH₂OH** → **CH₃CHO** (Product C)

### Final Product
The final product C is **CH₃CHO**, which is acetaldehyde.

### Summary of the Reaction Sequence
1. **CH₃CN** + **Na/C₂H₅OH** → **CH₃CH₂NH₂** (Product A)
2. **CH₃CH₂NH₂** + **HNO₂** → **CH₃CH₂OH** (Product B)
3. **CH₃CH₂OH** + **Cu/HOT, 573K** → **CH₃CHO** (Product C)

### Conclusion
The product C in the series is **CH₃CHO** (acetaldehyde), which corresponds to option 4.

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