CO is isoelectronic with

Options

A. `NO^(+)`
B. `N_(2)`
C. `SnCl_(2)`
D. `NO_(2)^(-).`

Explanation

To determine which species are isoelectronic with carbon monoxide (CO), we need to follow these steps:

### Step 1: Calculate the total number of electrons in CO
- Carbon (C) has an atomic number of 6, which means it has 6 electrons.
- Oxygen (O) has an atomic number of 8, which means it has 8 electrons.
- Therefore, the total number of electrons in CO is:
\[ \text{Total electrons in CO} = \text{Electrons from C} + \text{Electrons from O} = 6 + 8 = 14 \]

### Step 2: Identify isoelectronic species
Isoelectronic species are those that have the same number of electrons. We need to find species that also have 14 electrons.

#### a. Nitrogen ion (N⁺)
- Nitrogen (N) has an atomic number of 7, so it has 7 electrons.
- A nitrogen ion with a +1 charge (N⁺) has:
\[ \text{Electrons in N⁺} = 7 - 1 = 6 \]
- Therefore, if we consider a nitrogen molecule (N₂), which has two nitrogen atoms:
\[ \text{Electrons in N₂} = 7 \times 2 = 14 \]
- So, N₂ is isoelectronic with CO.

#### b. Nitric oxide ion (NO₂⁻)
- Nitrogen (N) has 7 electrons and oxygen (O) has 8 electrons.
- In NO₂⁻, we have one nitrogen and two oxygens, plus one extra electron due to the negative charge:
\[ \text{Electrons in NO₂⁻} = 7 + (8 \times 2) + 1 = 7 + 16 + 1 = 24 \]
- This species is not isoelectronic with CO.

#### c. Tin(II) chloride (SnCl₂)
- Tin (Sn) has an atomic number of 50 and chlorine (Cl) has an atomic number of 17.
- The total number of electrons in SnCl₂ is:
\[ \text{Electrons in SnCl₂} = 50 + (17 \times 2) = 50 + 34 = 84 \]
- This species is not isoelectronic with CO.

### Conclusion
The species that are isoelectronic with CO are:
- N₂ (Nitrogen molecule)
- N⁺ (Nitrogen ion)

### Final Answer
CO is isoelectronic with N₂ and N⁺.

---