Which of the following statement is incorrect?

Options

A. `O_(2)` is paramagnetic, `O_(3)` is also paramagnetic
B. `O_(2)` is paramagnetic, `O_(2)^(2-)` is diamagnetic
C. `B_(2)` is paramagnetic, `C_(2)` is also paramagnetic
D. Different obervation is found in their bond length when `NO to NO^(+) and CO to CO^(+)`

Explanation

To determine which statement is incorrect from the given options, we will analyze each statement one by one based on our knowledge of molecular orbital theory and the magnetic properties of molecules.

### Step 1: Analyze Option A
**Statement:** O2 is paramagnetic. O3 is also paramagnetic.

- **Analysis:**
- O2 (dioxygen) has two unpaired electrons in its molecular orbital configuration, which makes it paramagnetic.
- O3 (ozone), however, has all its electrons paired due to its resonance structures, making it diamagnetic.

**Conclusion:** This statement is incorrect.

### Step 2: Analyze Option B
**Statement:** O2 is paramagnetic where O2 2- is diamagnetic.

- **Analysis:**
- As previously established, O2 is indeed paramagnetic due to its two unpaired electrons.
- O2 2- (the superoxide ion) has all its electrons paired, making it diamagnetic.

**Conclusion:** This statement is correct.

### Step 3: Analyze Option C
**Statement:** B2 is paramagnetic and C2 is also paramagnetic.

- **Analysis:**
- B2 (diboron) has two unpaired electrons, making it paramagnetic.
- C2 (dicarbon), on the other hand, has all its electrons paired, which makes it diamagnetic.

**Conclusion:** This statement is incorrect.

### Step 4: Analyze Option D
**Statement:** Different observations are found in their bond lengths when NO converts to NO+ and CO converts to CO+.

- **Analysis:**
- When NO (nitric oxide) is converted to NO+, it loses an electron from an antibonding orbital, which affects its bond length.
- Similarly, CO (carbon monoxide) also shows a change in bond length when it loses an electron to form CO+.

**Conclusion:** This statement is correct.

### Final Conclusion
From the analysis, the incorrect statements are found in options A and C.

**Answer:** Options A and C are incorrect.

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