Answer :
To determine in which molecules nitrogen has a formal charge of zero, we need to analyze each molecule's structure and calculate the formal charge of nitrogen. We have three molecules to check: [tex]\( \text{NO}_2^- \)[/tex], [tex]\( \text{NO}_2 \)[/tex], and [tex]\( \text{NO}_2^+ \)[/tex]. Here is how we calculate the formal charge for each:
1. Formal Charge Formula:
[tex]\[
\text{Formal Charge (FC)} = V - N - \frac{B}{2}
\][/tex]
Where:
- [tex]\( V \)[/tex] is the number of valence electrons on the atom.
- [tex]\( N \)[/tex] is the number of non-bonding (lone pair) electrons.
- [tex]\( B \)[/tex] is the number of electrons shared in bonds (bonding electrons).
2. Nitrogen's Valence Electrons: Nitrogen typically has 5 valence electrons.
Now, let's analyze each molecule:
### 1. [tex]\( \text{NO}_2^- \)[/tex]:
- Nitrogen in [tex]\( \text{NO}_2^- \)[/tex]:
- Valence electrons ([tex]\( V \)[/tex]): 5
- Non-bonding electrons ([tex]\( N \)[/tex]): None listed
- Bonding electrons ([tex]\( B \)[/tex]): Typically two single bonds are considered, counting twice gives us 4 bonding electrons.
- Plug these into the formal charge formula.
### 2. [tex]\( \text{NO}_2 \)[/tex]:
- Nitrogen in [tex]\( \text{NO}_2 \)[/tex]:
- Valence electrons ([tex]\( V \)[/tex]): 5
- Non-bonding electrons ([tex]\( N \)[/tex]): None listed
- Bonding electrons ([tex]\( B \)[/tex]): Typically two single bonds are considered, counting twice gives us 4 bonding electrons.
- Use the formula as before.
### 3. [tex]\( \text{NO}_2^+ \)[/tex]:
- Nitrogen in [tex]\( \text{NO}_2^+ \)[/tex]:
- Valence electrons ([tex]\( V \)[/tex]): 5
- Non-bonding electrons ([tex]\( N \)[/tex]): None listed
- Bonding electrons ([tex]\( B \)[/tex]): Typically two single bonds are considered, counting twice gives us 4 bonding electrons.
- Apply the formula here as well.
After applying these calculations, nitrogen's formal charge in each of the three molecules is found to be 3.0. Therefore, nitrogen does not have a formal charge of zero in any of these molecules. So, the answer is that in none of these molecules does nitrogen have a formal charge of zero.
1. Formal Charge Formula:
[tex]\[
\text{Formal Charge (FC)} = V - N - \frac{B}{2}
\][/tex]
Where:
- [tex]\( V \)[/tex] is the number of valence electrons on the atom.
- [tex]\( N \)[/tex] is the number of non-bonding (lone pair) electrons.
- [tex]\( B \)[/tex] is the number of electrons shared in bonds (bonding electrons).
2. Nitrogen's Valence Electrons: Nitrogen typically has 5 valence electrons.
Now, let's analyze each molecule:
### 1. [tex]\( \text{NO}_2^- \)[/tex]:
- Nitrogen in [tex]\( \text{NO}_2^- \)[/tex]:
- Valence electrons ([tex]\( V \)[/tex]): 5
- Non-bonding electrons ([tex]\( N \)[/tex]): None listed
- Bonding electrons ([tex]\( B \)[/tex]): Typically two single bonds are considered, counting twice gives us 4 bonding electrons.
- Plug these into the formal charge formula.
### 2. [tex]\( \text{NO}_2 \)[/tex]:
- Nitrogen in [tex]\( \text{NO}_2 \)[/tex]:
- Valence electrons ([tex]\( V \)[/tex]): 5
- Non-bonding electrons ([tex]\( N \)[/tex]): None listed
- Bonding electrons ([tex]\( B \)[/tex]): Typically two single bonds are considered, counting twice gives us 4 bonding electrons.
- Use the formula as before.
### 3. [tex]\( \text{NO}_2^+ \)[/tex]:
- Nitrogen in [tex]\( \text{NO}_2^+ \)[/tex]:
- Valence electrons ([tex]\( V \)[/tex]): 5
- Non-bonding electrons ([tex]\( N \)[/tex]): None listed
- Bonding electrons ([tex]\( B \)[/tex]): Typically two single bonds are considered, counting twice gives us 4 bonding electrons.
- Apply the formula here as well.
After applying these calculations, nitrogen's formal charge in each of the three molecules is found to be 3.0. Therefore, nitrogen does not have a formal charge of zero in any of these molecules. So, the answer is that in none of these molecules does nitrogen have a formal charge of zero.
