Find the formal charge of ‘O’ in ozone.

To determine the formal charge of oxygen in ozone (O₃), we first need to understand its molecular structure. Ozone consists of three oxygen atoms, with one central atom bonded to two outer atoms.

Steps to Calculate Formal Charge

The formal charge can be calculated using the formula:

Formal Charge = Valence Electrons - (Non-bonding Electrons + 0.5 * Bonding Electrons)

1. Identify Valence Electrons

Oxygen has 6 valence electrons. In ozone, each oxygen atom contributes to the overall structure.

2. Count Non-bonding Electrons

The central oxygen atom in ozone has one lone pair (2 electrons), while the outer oxygen atoms have three lone pairs (6 electrons each).

3. Count Bonding Electrons

In ozone, there are two single bonds and one double bond. This means:

• Central oxygen: 4 bonding electrons (2 from the double bond and 2 from the single bond).
• Outer oxygen: 2 bonding electrons (from the single bond).

Calculating for Each Oxygen Atom

Central Oxygen

For the central oxygen:

• Valence Electrons: 6
• Non-bonding Electrons: 2
• Bonding Electrons: 4

Formal Charge = 6 - (2 + 0.5 * 4) = 6 - (2 + 2) = 2

Outer Oxygen

For each outer oxygen:

• Valence Electrons: 6
• Non-bonding Electrons: 6
• Bonding Electrons: 2

Formal Charge = 6 - (6 + 0.5 * 2) = 6 - (6 + 1) = -1

Summary of Formal Charges

In ozone, the formal charges are:

• Central Oxygen: +1
• Each Outer Oxygen: -1

This distribution of formal charges helps stabilize the molecule, making ozone an important component of the Earth's atmosphere.