Which one of the following nitroalkanes will give nitrolic acid with `NaNO_2//conc. H_2SO_4`

Options

A. `CH_3-underset(CH_3)underset(|)(CH)-NO_2`
B. `C_2H_5-underset(CH_3)underset(|)overset(CH_3)overset(|)C-NO_2`
C. `CH_3-underset(CH_3)underset(|)(CH)-CH_2-NO_2`
D. All of these

Answer

To determine which nitroalkane will yield nitrolic acid when reacted with NaNO2 and concentrated H2SO4, we need to identify the type of nitro compound present in the options provided. Nitrolic acid is formed from primary nitro compounds when they react with nitrous acid (HNO2), which is generated in situ from NaNO2 and H2SO4.

### Step-by-Step Solution:

1. **Identify the Type of Nitro Compounds**:
- Nitro compounds can be classified as primary, secondary, or tertiary based on the carbon atom to which the nitro group (NO2) is attached.
- Primary nitro compounds have the nitro group attached to a carbon that is connected to only one other carbon atom.
- Secondary nitro compounds have the nitro group attached to a carbon that is connected to two other carbon atoms.
- Tertiary nitro compounds have the nitro group attached to a carbon that is connected to three other carbon atoms.

2. **Analyze Each Compound**:
- **Compound A**: If the nitro group is attached to a carbon that has two other carbons, it is secondary and will not yield nitrolic acid.
- **Compound B**: If the nitro group is attached to a carbon that has three other carbons, it is tertiary and will not yield nitrolic acid.
- **Compound C**: If the nitro group is attached to a carbon that has only one other carbon, it is primary and can yield nitrolic acid.
- **Compound D**: Similar analysis as above to determine if it is primary, secondary, or tertiary.

3. **Determine the Reaction**:
- For the primary nitro compound identified, when it reacts with nitrous acid (HNO2), it will undergo a reaction to form nitrolic acid.
- The reaction involves the loss of water and the formation of a double bond between nitrogen and carbon, resulting in the structure of nitrolic acid.

4. **Conclusion**:
- After analyzing all the compounds, the primary nitro compound is the one that will yield nitrolic acid upon reaction with NaNO2 and concentrated H2SO4.

### Final Answer:
The nitroalkane that will give nitrolic acid is the primary nitro compound identified in the options.