Which of the following are isoelectronic and isostructural ?
`NO_(3)^(-) , CO_(3)^(2-),ClO_(3)^(-),SO_(3)`

Options

A. `NO_(3)^(-),CO_(3)^(2-)`
B. `SO_(3),NO_(3)^(-)`
C. `ClO_(3),CO_(3)^(2-)`
D. `CO_(3)^(2-),SO_(3)`

Explanation

To determine which of the given species are isoelectronic and isostructural, we will analyze each species: \( NO_3^- \), \( CO_3^{2-} \), \( ClO_3^- \), and \( SO_3 \).

### Step 1: Calculate the total number of electrons for each species.

1. **For \( NO_3^- \)**:
- Nitrogen (N) has 7 electrons.
- Oxygen (O) has 8 electrons, and there are 3 oxygen atoms.
- The negative charge adds 1 electron.
- Total = \( 7 + (3 \times 8) + 1 = 7 + 24 + 1 = 32 \) electrons.

2. **For \( CO_3^{2-} \)**:
- Carbon (C) has 6 electrons.
- Oxygen (O) has 8 electrons, and there are 3 oxygen atoms.
- The 2 negative charges add 2 electrons.
- Total = \( 6 + (3 \times 8) + 2 = 6 + 24 + 2 = 32 \) electrons.

3. **For \( ClO_3^- \)**:
- Chlorine (Cl) has 17 electrons.
- Oxygen (O) has 8 electrons, and there are 3 oxygen atoms.
- The negative charge adds 1 electron.
- Total = \( 17 + (3 \times 8) + 1 = 17 + 24 + 1 = 42 \) electrons.

4. **For \( SO_3 \)**:
- Sulfur (S) has 16 electrons.
- Oxygen (O) has 8 electrons, and there are 3 oxygen atoms.
- Total = \( 16 + (3 \times 8) = 16 + 24 = 40 \) electrons.

### Summary of Total Electrons:
- \( NO_3^- \): 32 electrons
- \( CO_3^{2-} \): 32 electrons
- \( ClO_3^- \): 42 electrons
- \( SO_3 \): 40 electrons

### Step 2: Identify isoelectronic species.
From the calculations, we see that \( NO_3^- \) and \( CO_3^{2-} \) both have 32 electrons, making them isoelectronic.

### Step 3: Determine the structure of each species.
1. **\( NO_3^- \)**:
- The structure is trigonal planar with \( sp^2 \) hybridization.

2. **\( CO_3^{2-} \)**:
- The structure is also trigonal planar with \( sp^2 \) hybridization.

3. **\( ClO_3^- \)**:
- The structure is pyramidal with \( sp^3 \) hybridization due to the presence of a lone pair.

4. **\( SO_3 \)**:
- The structure is trigonal planar with \( sp^2 \) hybridization.

### Step 4: Identify isostructural species.
Since both \( NO_3^- \) and \( CO_3^{2-} \) are trigonal planar, they are also isostructural.

### Conclusion:
The species that are isoelectronic and isostructural are \( NO_3^- \) and \( CO_3^{2-} \).

### Final Answer:
**\( NO_3^- \) and \( CO_3^{2-} \)** are the isoelectronic and isostructural species.

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