In the reaction
`R-overset(O)overset(||)(C)-OHoverset(H_(3)O^(+))rarrXoverset((H))rarrRCH_(2)NH_(2),'X'` is

Options

A. Isonitrile
B. Nitrile
C. Nitrite
D. Oxime

Explanation

To solve the question, we need to identify the compound 'X' in the given reaction sequence. Let's break down the steps:

### Step 1: Identify the starting compound
The starting compound is given as `R-C(=O)-OH` which is a carboxylic acid. The presence of `H3O+` indicates that we are dealing with an acidic medium.

### Step 2: Understand the reaction with H3O+
When a carboxylic acid reacts with `H3O+`, it can undergo hydrolysis or other reactions, but in this case, we are looking for a transformation that leads to a nitrogen-containing compound.

### Step 3: Identify the intermediate compound 'X'
The reaction suggests that 'X' is likely to be an amide or an intermediate leading to an amine. Since we are reducing 'X' to form `RCH2NH2`, it indicates that 'X' must contain a carbonyl group (C=O) and a nitrogen atom.

### Step 4: Determine the structure of 'X'
Given that we are starting with a carboxylic acid and ending with a primary amine, 'X' is likely to be an amide. The structure can be represented as `R-C(=O)-NH2`.

### Step 5: Confirm the reduction process
When 'X' (the amide) is reduced, it will yield `RCH2NH2` (a primary amine). This reduction can be achieved using reagents like lithium aluminum hydride (LiAlH4) or sodium in ethanol (Na + C2H5OH), which is consistent with the reduction mentioned in the video transcript.

### Conclusion
Thus, the compound 'X' is an amide, specifically `R-C(=O)-NH2`.

### Final Answer
**X = R-C(=O)-NH2 (Amide)**

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