Question

determine the formal charge for the left oxygen atom, the central carbon atom and the top oxygen atom in this structure.
o on left:
central c:
o on top:

Explanation:

The formula for formal charge is \( \text{Formal Charge} = \text{Valence Electrons} - \text{Non - bonding Electrons} - \frac{1}{2}\text{Bonding Electrons} \)

Step 1: Determine formal charge of left O

• Valence electrons of O: \( 6 \)
• Non - bonding electrons: The left O has \( 6 \) non - bonding electrons (from the Lewis structure: 3 lone pairs, \( 3\times2 = 6 \))
• Bonding electrons: It is single - bonded to C, so bonding electrons \( = 2 \)
• Formal charge \(=6 - 6-\frac{2}{2}=6 - 6 - 1=- 1\)

Step 2: Determine formal charge of central C

• Valence electrons of C: \( 4 \)
• Non - bonding electrons: C has \( 0 \) non - bonding electrons (no lone pairs)
• Bonding electrons: C is bonded to two O atoms (one single bond and one double bond) and one O atom (single bond). Total bonding electrons: \( 2 + 4+2=8 \) (single bond has 2 electrons, double bond has 4 electrons)
• Formal charge \(=4 - 0-\frac{8}{2}=4 - 0 - 4 = 0\)

Step 3: Determine formal charge of top O

• Valence electrons of O: \( 6 \)
• Non - bonding electrons: The top O has \( 6 \) non - bonding electrons (3 lone pairs)
• Bonding electrons: It is single - bonded to C, so bonding electrons \( = 2 \)
• Formal charge \(=6 - 6-\frac{2}{2}=6 - 6 - 1=-1\)

Answer:

O on left: \(-1\)
central C: \(0\)
O on top: \(-1\)