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

Options

A. `NO_(3)^(ɵ), CO_(3)^(2-), ClO_(3)^(ɵ)`
B. `NO_(3)^(ɵ), CO_(3)^(2-), SO_(2)`
C. `CO_(3)^(2-), ClO_(3)^(ɵ), SO_(2)`
D. None of these

Explanation

To determine which of the given species are isoelectronic, we need to calculate the total number of electrons for each species. Isoelectronic species are those that have the same number of electrons.

### 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 electrons = \( 7 + (3 \times 8) + 1 = 7 + 24 + 1 = 32 \) 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 electrons = \( 6 + (3 \times 8) + 2 = 6 + 24 + 2 = 32 \) 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 electrons = \( 17 + (3 \times 8) + 1 = 17 + 24 + 1 = 42 \) electrons.

4. **For \( SO_2 \)**:
- Sulfur (S) has 16 electrons.
- Oxygen (O) has 8 electrons, and there are 2 oxygen atoms.
- Total electrons = \( 16 + (2 \times 8) = 16 + 16 = 32 \) electrons.

### Step 2: Compare the total number of electrons.
- \( NO_3^{-} \): 32 electrons
- \( CO_3^{2-} \): 32 electrons
- \( ClO_3^{-} \): 42 electrons
- \( SO_2 \): 32 electrons

### Conclusion:
The species that are isoelectronic (having the same number of electrons) are \( NO_3^{-} \), \( CO_3^{2-} \), and \( SO_2 \). Therefore, the correct answer is the option containing \( NO_3^{-} \), \( CO_3^{2-} \), and \( SO_2 \).

### Final Answer:
The isoelectronic species are \( NO_3^{-} \), \( CO_3^{2-} \), and \( SO_2 \).

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