Among the structures given below which one represents nitrolic acid?

Options

A. `R_2-N-N=O`
B. `R-overset(NO_2)overset(|)C=NOH`
C.
D. `R_2C=NOH`

Answer

To determine which structure represents nitrolic acid, we can follow these steps:

### Step 1: Understand the Structure of Nitrolic Acid
Nitrolic acid is characterized by the presence of a nitro group (-NO2) and a hydroxyl group (-OH) attached to a carbon atom. The general structure can be represented as R-C(=NOH)-NO2, where R is a hydrocarbon group.

### Step 2: Identify the Reaction Involved
Nitrolic acid can be formed by the reaction of a nitro compound with nitrous acid (HONO). This reaction typically involves the conversion of a nitro compound into nitrolic acid, which is often observed in the Victor Meyer test.

### Step 3: Recall the Victor Meyer Test
The Victor Meyer test is used to distinguish between primary, secondary, and tertiary alcohols. In this test, nitrous acid (generated from sodium nitrite and hydrochloric acid) reacts with the alcohol to form nitrolic acid.

### Step 4: Analyze the Given Structures
Now, we need to look at the structures provided in the question and identify which one matches the characteristics of nitrolic acid. We are looking for a structure that has:
- A carbon atom double-bonded to a nitrogen atom (C=NOH)
- A hydroxyl group (-OH) attached to the same carbon
- A nitro group (-NO2) attached to the carbon or nearby

### Step 5: Select the Correct Structure
After analyzing the given options, we select the structure that matches the description of nitrolic acid. According to the video transcript, the correct structure is the one that resembles a pseudo-nitrol, which is typically represented as C=NOH with a nitro group.

### Conclusion
The structure that represents nitrolic acid is the one that has the C=NOH configuration along with the nitro group. Based on the analysis, **Option 2** is the correct answer.

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