How many valid resonance structures can be drawn for the ozone molecule (O3)?

• A. 4
• B. 2
• C. 1
• D. 3

Answer: (B)

Verified step by step guidance

1. Step 1: Understand what resonance structures are. Resonance structures are different Lewis structures for the same molecule that show the same arrangement of atoms but different placements of electrons, especially pi bonds and lone pairs.
2. Step 2: Draw the Lewis structure of ozone (O3). Ozone has 18 valence electrons (6 from each oxygen atom). Arrange the three oxygen atoms in a row and connect them with single bonds initially.
3. Step 3: Distribute the remaining electrons to satisfy the octet rule for each oxygen atom. You will find that one oxygen will have a double bond with one neighbor and a single bond with the other, with lone pairs completing the octets.
4. Step 4: Identify the possible resonance structures by moving the double bond between the central oxygen and the terminal oxygens. This means the double bond can be on the left side or the right side, while the other side has a single bond.
5. Step 5: Count the valid resonance structures. Since the double bond can be on either side, there are two valid resonance structures for ozone.