`CH_(3)CH_(2)NO_(2) underset(at 0^(@)C)overset(NaNO_(2)+HBr)(rarr) (A)`. `(A)` is

Options

A. a.`CH_(3)CH_(2)OH`
B. b.`CH_(3)CH_(2)OH`
C. c.`CH_(3)underset(NO_(2))underset(|)(C )=N.OH`
D. d.`No reaction`

Explanation

To solve the question regarding the reaction of CH₃CH₂NO₂ with NaNO₂ and HBr at 0°C, we will follow these steps:

### Step 1: Identify the reactants
The reactants in this reaction are:
- CH₃CH₂NO₂ (ethyl nitrite)
- NaNO₂ (sodium nitrite)
- HBr (hydrobromic acid)

### Step 2: Understand the reaction conditions
The reaction is carried out at 0°C (273 K), which is important for controlling the reaction pathway. Under these conditions, the nitro compound can undergo a specific reaction with nitrous acid (HNO₂) generated from NaNO₂ and HBr.

### Step 3: Reaction of NaNO₂ and HBr
When NaNO₂ reacts with HBr, it forms nitrous acid (HNO₂) and sodium bromide (NaBr):
\[ \text{NaNO}_2 + \text{HBr} \rightarrow \text{HNO}_2 + \text{NaBr} \]

### Step 4: Reaction of ethyl nitrite with nitrous acid
The nitro compound CH₃CH₂NO₂ reacts with nitrous acid (HNO₂) to form nitrolic acid. The reaction involves the formation of a hydroxylamine intermediate, which subsequently loses a water molecule (dehydration) to yield the final product.

### Step 5: Formation of nitrolic acid
The reaction can be summarized as follows:
1. The nitro compound (CH₃CH₂NO₂) reacts with HNO₂.
2. A hydroxylamine intermediate is formed.
3. Elimination of water occurs, leading to the formation of nitrolic acid.

The structure of the product (A) can be represented as:
\[ \text{CH}_3\text{C}=\text{N}\text{O}_2\text{H} \]
This compound is known as nitrolic acid.

### Step 6: Conclusion
The product (A) formed from the reaction of CH₃CH₂NO₂ with NaNO₂ and HBr at 0°C is nitrolic acid.

### Final Answer
The product (A) is **Nitrolic Acid (CH₃C(NO₂)=OH)**.

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