The species in which the N-atom is in a state of sp hybridisation is

Options

A. `NO_(3)^(-)`
B. `NO_(2)`
C. `NO_(2)^(+)`
D. `NO_(2)^(-)`

Answer

To determine which species has a nitrogen atom in the state of sp hybridization, we will analyze the hybridization of nitrogen in each given species step by step.

### Step 1: Analyze NO3⁻ (Nitrate Ion)
- Structure: The nitrate ion has one nitrogen atom bonded to three oxygen atoms. The nitrogen forms one double bond with one oxygen and two single bonds with the other two oxygens. There is also a coordinate bond with one of the oxygens.
- Hybridization: The nitrogen in NO3⁻ has three sigma bonds and no lone pairs. This results in sp² hybridization because the hybridization can be determined by the formula:
\[ \text{Hybridization} = \text{Number of sigma bonds} + \frac{\text{Number of lone pairs}}{2} \]
Here, it is \(3 + 0 = 3\) which corresponds to sp².

### Step 2: Analyze NO2 (Nitrogen Dioxide)
- Structure: The nitrogen atom in NO2 is bonded to two oxygen atoms, one with a double bond and the other with a single bond. There is also one unpaired electron (odd electron).
- Hybridization: The nitrogen has two sigma bonds and one unpaired electron can be considered as a third bond. Thus, it also has sp² hybridization because it has three effective bonds (2 sigma + 1 unpaired).

### Step 3: Analyze NO2⁺ (Nitronium Ion)
- Structure: The nitronium ion has nitrogen bonded to two oxygen atoms with double bonds. It does not have any lone pairs.
- Hybridization: The nitrogen atom in NO2⁺ has two sigma bonds (one with each oxygen) and no lone pairs. Therefore, it has sp hybridization, as it corresponds to:
\[ \text{Hybridization} = 2 + 0 = 2 \]

### Step 4: Analyze NO2⁻ (Nitrite Ion)
- Structure: The nitrite ion has nitrogen bonded to two oxygen atoms, one with a double bond and one with a single bond. There is also one lone pair on nitrogen.
- Hybridization: The nitrogen has two sigma bonds and one lone pair. Thus, it has sp² hybridization:
\[ \text{Hybridization} = 2 + 1 = 3 \]

### Conclusion
From the analysis:
- NO3⁻: sp² hybridization
- NO2: sp² hybridization
- NO2⁺: sp hybridization (this is the only species with sp hybridization)
- NO2⁻: sp² hybridization

Thus, the species in which the nitrogen atom is in a state of sp hybridization is **NO2⁺**.

### Final Answer
The species in which the N-atom is in a state of sp hybridization is **NO2⁺**.

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