Among the following , the paramagnetic compound is :

Options

A. `Na_2O_2`
B. ` O^3`
C. ` N_2O`
D. `KO_2`

Explanation

To determine which of the given compounds is paramagnetic, we need to identify whether they contain unpaired electrons. A paramagnetic compound has one or more unpaired electrons, while a diamagnetic compound has all its electrons paired.

Let's analyze each option step by step:

### Step 1: Analyze Na2O2
- **Composition**: Na2O2 consists of sodium (Na) and peroxide (O2^2-).
- **Sodium (Na)**: Na has an atomic number of 11, with an electron configuration of 1s² 2s² 2p⁶ 3s¹. In Na⁺, it loses one electron and has a filled shell configuration (1s² 2s² 2p⁶).
- **Peroxide (O2^2-)**: Each oxygen in O2^2- contributes 8 electrons (1s² 2s² 2p⁶), resulting in a total of 10 electrons. All electrons are paired.
- **Conclusion**: Na2O2 is diamagnetic.

### Step 2: Analyze Ozone (O3)
- **Structure**: Ozone has a bent structure with a resonance hybrid of two forms.
- **Electron Configuration**: Ozone has a total of 18 electrons (6 from each oxygen).
- **Filling of Orbitals**: All electrons in ozone are paired.
- **Conclusion**: Ozone is also diamagnetic.

### Step 3: Analyze N2O
- **Structure**: N2O has a linear structure with a double bond between nitrogen atoms and a single bond with oxygen.
- **Electron Configuration**: Nitrogen has 7 electrons, and there are 2 nitrogen atoms and 1 oxygen atom, giving a total of 20 electrons.
- **Filling of Orbitals**: All electrons are paired in N2O.
- **Conclusion**: N2O is diamagnetic.

### Step 4: Analyze KO2 (Potassium Superoxide)
- **Composition**: KO2 consists of potassium (K) and superoxide (O2^-).
- **Potassium (K)**: K has an atomic number of 19, with an electron configuration of 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹. K⁺ has a filled shell configuration (1s² 2s² 2p⁶ 3s² 3p⁶).
- **Superoxide (O2^-)**: The superoxide ion has 9 electrons (O2 has 12 electrons, and one additional electron is added). The configuration is 1s² 2s² 2p⁴ for the two oxygen atoms, and one extra electron makes it 2p⁵.
- **Filling of Orbitals**: When filling the orbitals, one of the electrons in the 2p orbital will remain unpaired.
- **Conclusion**: KO2 is paramagnetic due to the presence of unpaired electrons.

### Final Answer
The paramagnetic compound among the options is **KO2**.

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