A filled or half-filled set of p or d -orbitals is spherically symmetric. Point out the species which has spherical symmetry

Options

A. Na
B. C
C. `Cl^(-)`
D. Fe

Explanation

To determine which species have spherical symmetry due to filled or half-filled p or d orbitals, we can follow these steps:

### Step 1: Understand Spherical Symmetry
Spherical symmetry in atomic orbitals means that the electron density is evenly distributed in all directions around the nucleus. This occurs when orbitals are completely filled or half-filled.

### Step 2: Identify the Given Species
The species mentioned are:
1. Sodium (Na)
2. Carbon (C)
3. Chlorine ion (Cl⁻)
4. Iron (Fe)

### Step 3: Analyze Each Species
- **Sodium (Na)**: Sodium has the electron configuration of [Ne]3s¹. The 3s orbital is not filled, and there are no p or d orbitals that are filled or half-filled. Thus, Na does not have spherical symmetry.

- **Carbon (C)**: Carbon has the electron configuration of 1s² 2s² 2p². The 2p orbitals are not filled or half-filled (they have 2 out of 6 possible electrons). Therefore, C does not exhibit spherical symmetry.

- **Chlorine ion (Cl⁻)**: Chlorine has the electron configuration of [Ne]3s² 3p⁶. When it gains an electron to become Cl⁻, it has a filled p orbital configuration (3p⁶). Since the p orbitals are completely filled, Cl⁻ exhibits spherical symmetry.

- **Iron (Fe)**: Iron has the electron configuration of [Ar] 4s² 3d⁶. The 3d orbitals are not completely filled (there are 6 out of 10 possible electrons). Therefore, Fe does not have spherical symmetry.

### Step 4: Conclusion
Among the given species, only the chlorine ion (Cl⁻) has spherical symmetry due to its filled p orbitals.

### Final Answer
The species that has spherical symmetry is **Chlorine ion (Cl⁻)**.

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