write the lewis structure for dinitrogen oxide. include the 2 resonance structures and formal charges where appropriate.
http://wiki.answers.com/Q/What_is_the_lewis_structure_of_N2O
To draw the Lewis structure of dinitrogen oxide (N2O), we need to determine the total number of valence electrons.
Nitrogen (N) is in Group 15 of the periodic table, so each nitrogen atom contributes 5 valence electrons. Since we have two nitrogen atoms, the total number of valence electrons from nitrogen is 2 x 5 = 10.
Oxygen (O) is in Group 16, and it contributes 6 valence electrons.
Therefore, the total number of valence electrons for dinitrogen oxide is 10 + 6 = 16.
Now let's draw the Lewis structure:
1. Start by connecting the nitrogen atoms with a single bond (N≡N).
N≡N
2. Distribute the remaining valence electrons around the atoms to fulfill the octet rule (except for hydrogen, which follows the duet rule).
Since we have 16 valence electrons, we place them as follows:
N≡N
. . .
We have two electrons left.
3. Place the remaining two electrons on the oxygen atom.
N≡N
. O ..
4. Check if all atoms have an octet (except hydrogen). In this case, nitrogen has only 5 electrons, which is less than 8, so it can accept electrons to fulfill the octet.
We can draw two resonance structures by taking one electron from each nitrogen atom and forming a double bond with the oxygen atom:
N≡N
. . ..
∆
N=N
. . ..
∆
5. Check for formal charges to verify the stability of each resonance structure.
In the first resonance structure, the nitrogen bonded to oxygen has 6 electrons (including the two shared electrons in the double bond) and the other nitrogen has 7 electrons. Since neutral nitrogen should have 5 valence electrons, both are negatively charged (-1 for each nitrogen). Oxygen has 6 electrons and should have 6 valence electrons, so it has no formal charge.
In the second resonance structure, both nitrogen atoms have 6 valence electrons (including the double bond with oxygen), which is their neutral electron count. Oxygen also has no formal charge.
The formal charges are as follows:
N(-1)=N(-1)=O(0) ↔ N(-1)=N(0)-O(-1)
So, the Lewis structure for dinitrogen oxide (N2O) includes the two resonance structures depicted above, along with the formal charges indicated.