In the series of reactions `CH_3 COOH underset(P_2O_5)overset(NH_3)to A`
`A overset"Heat"to B overset(P_2O_5)to C` the end product C is

Options

A. `CH_4`
B. acetonitrile
C. `CH_3OH`
D. methyl cyanate

Explanation

To solve the problem step by step, we will analyze each reaction in the series provided.

### Step 1: Reaction of Acetic Acid with Ammonia and P2O5
The first reaction involves acetic acid (CH₃COOH) reacting with ammonia (NH₃) in the presence of phosphorus pentoxide (P₂O₅).

- **Reaction**:
\[ \text{CH}_3\text{COOH} + \text{NH}_3 \xrightarrow{\text{P}_2\text{O}_5} \text{CH}_3\text{CONH}_4 \]
- **Product A**: The product formed is ammonium acetate (CH₃CONH₄).

### Step 2: Heating Product A to Form Product B
Next, we heat product A (ammonium acetate).

- **Reaction**:
\[ \text{CH}_3\text{CONH}_4 \xrightarrow{\text{Heat}} \text{CH}_3\text{CONH}_2 + \text{H}_2\text{O} \]
- **Product B**: The product formed is acetamide (CH₃CONH₂).

### Step 3: Reaction of Product B with P2O5 to Form Product C
Finally, product B (acetamide) reacts with P₂O₅.

- **Reaction**:
\[ \text{CH}_3\text{CONH}_2 \xrightarrow{\text{P}_2\text{O}_5} \text{CH}_3\text{CN} + \text{H}_2\text{O} \]
- **Product C**: The end product formed is acetonitrile (CH₃CN).

### Final Answer
The end product C is **acetonitrile (CH₃CN)**.

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