Sure, let's analyze the importance of the given resonance structure for dinitrogen monoxide (N₂O).
### Step-by-Step Solution:
1. Understanding Resonance Structures:
Resonance structures are different possible structures for a molecule where the arrangement of electrons varies, but the arrangement of atoms remains the same. The resonance hybrid is a blend of all possible resonance structures, contributing to the overall characteristics of the molecule.
2. Given Resonance Structure:
The structure given is:
[tex]\[
: \ddot{ N }- N \equiv O \text { : }
\][/tex]
3. Assessing Stability Based on Formal Charges:
To determine the stability and importance of a resonance structure, we consider formal charges.
- Formal charges are calculated using the formula:
[tex]\[
\text{Formal charge} = (\text{Valence electrons}) - (\text{Non-bonding electrons}) - \frac{1}{2} \times (\text{Bonding electrons})
\][/tex]
- For the left nitrogen (N):
- Valence electrons = 5
- Non-bonding electrons = 4 (two lone pairs)
- Bonding electrons = 2 (single bond)
- Formal charge = [tex]\( 5 - 4 - \frac{1}{2} \times 2 = 0 \)[/tex]
- For the central nitrogen (N):
- Valence electrons = 5
- Non-bonding electrons = 0
- Bonding electrons = 8 (single bond to N, triple bond to O)
- Formal charge = [tex]\( 5 - 0 - \frac{1}{2} \times 8 = 1 \)[/tex]
- For the oxygen (O):
- Valence electrons = 6
- Non-bonding electrons = 4 (two lone pairs)
- Bonding electrons = 4 (triple bond to N)
- Formal charge = [tex]\( 6 - 4 - \frac{1}{2} \times 4 = 0 \)[/tex]
4. Checking for Octet Fulfillment:
- Each atom in the molecule should ideally satisfy the octet rule (having 8 electrons in the valence shell).
- The left nitrogen has 8 valence electrons (4 non-bonding + 2 bonding pairs).
- The central nitrogen has 8 electrons (satisfied by the single bond with left N and the triple bond with O).
- The oxygen has 8 valence electrons (4 non-bonding + 4 bonding).
5. Electronegativity Considerations:
- Stability is increased when negative formal charges are placed on more electronegative atoms.
- Oxygen is more electronegative than nitrogen, and it's preferable to have the formal charges arranged such that they reflect this property.
6. Overall Contribution to Resonance Hybrid:
- Given the above stability checks, the structure minimizes formal charges and maintains the octet rule.
- Since it satisfies these criteria and the resonance structure is significant and stable, it likely contributes considerably to the resonance hybrid.
### Conclusion:
The resonance structure
[tex]\[
: \ddot{ N }- N \equiv O \text { : }
\][/tex]
is a significant contributor to the overall resonance hybrid of dinitrogen monoxide, enhancing the molecule's overall stability.
