Which of the following is the correct Lewis dot structure for the neutral compound carbon dioxide (CO_2)?

• A. O=C=O, with each O atom having two lone pairs
• B. O–C≡O, with the central C atom having two lone pairs
• C. O–C–O, with each O atom having three lone pairs
• D. O≡C–O, with one O atom having one lone pair and the other having three lone pairs

Answer: (A)

Verified step by step guidance

1. Step 1: Determine the total number of valence electrons available for the molecule. Carbon (C) has 4 valence electrons, and each oxygen (O) has 6 valence electrons. Since there are two oxygen atoms, total valence electrons = 4 + 2 × 6 = 16 electrons.
2. Step 2: Arrange the atoms with carbon as the central atom because it is less electronegative than oxygen. Connect the carbon atom to each oxygen atom with single bonds initially.
3. Step 3: Distribute the remaining valence electrons to satisfy the octet rule for the outer atoms (oxygen atoms first). Each oxygen should have 8 electrons around it (including bonding electrons), typically achieved by adding lone pairs.
4. Step 4: Check if the central atom (carbon) has a complete octet. If not, form double or triple bonds by converting lone pairs from oxygen atoms into bonding pairs between carbon and oxygen until carbon has 8 electrons.
5. Step 5: Verify the final Lewis structure by counting all electrons to ensure the total matches the valence electrons calculated in Step 1, and confirm that each atom (except hydrogen, if present) has a full octet.