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:
\[ \text{Total electrons in CO} = 6 + 8 = 14 \]

### Step 2: Check the first option: NO positive (NO⁺)
- Nitrogen (N) has an atomic number of 7, so it has 7 electrons.
- Oxygen (O) has 8 electrons.
- The positive charge indicates that one electron is lost. Thus, the total number of electrons is:
\[ \text{Total electrons in NO} = 7 + 8 - 1 = 14 \]
- Therefore, NO⁺ is isoelectronic with CO.

### Step 3: Check the second option: N2
- Each nitrogen atom has 7 electrons. Since there are two nitrogen atoms:
\[ \text{Total electrons in N2} = 7 + 7 = 14 \]
- Therefore, N2 is also isoelectronic with CO.

### Step 4: Check the third option: SnCl2
- Tin (Sn) has an atomic number of 50, so it has 50 electrons.
- Chlorine (Cl) has an atomic number of 17, so each chlorine has 17 electrons. Since there are two chlorine atoms:
\[ \text{Total electrons in SnCl2} = 50 + (17 \times 2) = 50 + 34 = 84 \]
- Therefore, SnCl2 is not isoelectronic with CO.

### Step 5: Check the fourth option: NO2 negative (NO2⁻)
- Nitrogen (N) has 7 electrons.
- Each oxygen (O) has 8 electrons, and there are two oxygen atoms:
\[ \text{Total electrons in NO2} = 7 + (8 \times 2) + 1 = 7 + 16 + 1 = 24 \]
- Therefore, NO2⁻ is not isoelectronic with CO.

### Conclusion
The species that are isoelectronic with CO are:
- NO⁺ (14 electrons)
- N2 (14 electrons)