IDNLearn.com offers a comprehensive platform for finding and sharing knowledge. Our platform offers detailed and accurate responses from experts, helping you navigate any topic with confidence.

What are the formal charges on nitrogen and on the starred oxygen in the following species?

A. [tex]\( N = -1, O = -1 \)[/tex]
B. [tex]\( N = +1, O = 0 \)[/tex]
C. [tex]\( N = +1, O = -1 \)[/tex]
D. [tex]\( N = +1, O = +1 \)[/tex]
E. [tex]\( N = -1, O = 0 \)[/tex]


Sagot :

To find the formal charges on nitrogen (N) and the starred oxygen (O) in a given molecule, we follow these steps:

1. Determine the number of valence electrons for each atom:
- Nitrogen (N) has 5 valence electrons.
- Oxygen (O) has 6 valence electrons.

2. Identify the bonding and non-bonding electrons around each atom:
- Bonding electrons are those involved in covalent bonds.
- Non-bonding electrons (also called lone pairs) are those not involved in bonding and are just on a single atom.

3. Use the formula for formal charge:
[tex]\[ \text{Formal charge} = (\text{Valence electrons}) - (\text{Non-bonding electrons}) - \left(\frac{\text{Bonding electrons}}{2}\right) \][/tex]

### Calculation for Nitrogen (N):
If nitrogen is forming four covalent bonds (as in a structure like NH4+):

- Valence electrons for nitrogen (N) = 5
- Non-bonding electrons on nitrogen = 0 (since all electrons are involved in bonding)
- Bonding electrons on nitrogen = 8 (4 bonds, each bond has 2 electrons)

[tex]\[ \text{Formal charge on N} = 5 - 0 - \left(\frac{8}{2}\right) = 5 - 0 - 4 = +1 \][/tex]

### Calculation for the starred Oxygen (O):
If the starred oxygen is forming one covalent bond and has three lone pairs (like in a structure with an -O- connection):

- Valence electrons for oxygen (O) = 6
- Non-bonding electrons on oxygen = 6 (3 lone pairs * 2 electrons each)
- Bonding electrons on oxygen = 2 (1 bond, bond has 2 electrons)

[tex]\[ \text{Formal charge on O} = 6 - 6 - \left(\frac{2}{2}\right) = 6 - 6 - 1 = -1 \][/tex]

Based on these calculations, the formal charges are:

- Nitrogen (N): +1
- Starred Oxygen (O): -1

So, the correct answer is:
[tex]\[ N=+1, O=-1 \][/tex]