Which of the following is paramagnetic

Options

A. NO
B. `NO_(2)`
C. `ClO_(2)`
D. All

Explanation

To determine which of the compounds (NO, NO2, ClO2) is paramagnetic, we need to analyze the number of valence electrons in each compound and check for unpaired electrons. Here's a step-by-step solution:

### Step 1: Identify the valence electrons in each compound.
- **Nitric Oxide (NO)**:
- Nitrogen (N) has 5 valence electrons.
- Oxygen (O) has 6 valence electrons.
- Total = 5 + 6 = 11 valence electrons.

- **Chlorine Dioxide (ClO2)**:
- Chlorine (Cl) has 7 valence electrons.
- Each Oxygen (O) has 6 valence electrons, and there are 2 Oxygens.
- Total = 7 + (2 × 6) = 7 + 12 = 19 valence electrons.

- **Sodium Peroxide (NaO2)**:
- Sodium (Na) has 1 valence electron.
- Each Oxygen (O) has 6 valence electrons, and there are 2 Oxygens.
- Total = 1 + (2 × 6) = 1 + 12 = 13 valence electrons.

### Step 2: Determine if the total number of valence electrons is odd or even.
- **NO**: 11 (odd)
- **ClO2**: 19 (odd)
- **NaO2**: 13 (odd)

### Step 3: Analyze the magnetic properties based on the number of valence electrons.
- A compound is **paramagnetic** if it has unpaired electrons, which typically occurs when the total number of valence electrons is odd.
- Since all three compounds have an odd number of valence electrons, they will have unpaired electrons.

### Conclusion:
All three compounds (NO, ClO2, NaO2) are paramagnetic due to having an odd number of valence electrons, which indicates the presence of unpaired electrons.

### Final Answer:
**All of the compounds (NO, ClO2, NaO2) are paramagnetic.**

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