The species having bond order different from that in `CO` is

Options

A. `NO^(-)`
B. `NO^(+)`
C. `CN^(-)`
D. `N_(2).`

Explanation

To determine which species has a bond order different from that of carbon monoxide (CO), we first need to calculate the bond order of CO and then compare it with the bond orders of other given species.

### Step 1: Calculate the bond order of CO
1. **Count the total number of electrons in CO**:
- Carbon (C) has 6 electrons.
- Oxygen (O) has 8 electrons.
- Total = 6 (C) + 8 (O) = 14 electrons.

2. **Determine the bond order using the formula**:
\[ \text{Bond Order} = \frac{(\text{Number of bonding electrons} - \text{Number of antibonding electrons})}{2} \]
For CO, the molecular orbital configuration is:
- Bonding orbitals: 10 electrons (σ2s, σ*2s, σ2p, π2p)
- Antibonding orbitals: 4 electrons (π*2p)
- Bond order = (10 - 4) / 2 = 3.

### Step 2: Analyze other species
1. **NO- (Nitric oxide anion)**:
- Total electrons = 7 (N) + 8 (O) + 1 (extra electron) = 16 electrons.
- Bond order can be calculated similarly, and it will be found to be 2.

2. **NO+ (Nitric oxide cation)**:
- Total electrons = 7 (N) + 8 (O) - 1 (lost electron) = 14 electrons.
- Bond order = 3 (same as CO).

3. **CN- (Cyanide anion)**:
- Total electrons = 6 (C) + 7 (N) + 1 (extra electron) = 14 electrons.
- Bond order = 3 (same as CO).

4. **N2 (Diatomic nitrogen)**:
- Total electrons = 7 (N) + 7 (N) = 14 electrons.
- Bond order = 3 (same as CO).

### Conclusion
The only species with a bond order different from that of CO is **NO-**, which has a bond order of 2.

### Final Answer
The species having bond order different from that in CO is **NO-**.