Final Answer:
The Lewis structure for the formaldehyde molecule (CH₂O) includes a carbon atom double-bonded to an oxygen atom and a hydrogen atom. There is an additional resonance structure where the double bond is shifted to the other side of the carbon atom, satisfying the octet rule for both carbon and oxygen.
Step-by-step explanation:
In the Lewis structure for formaldehyde, the carbon atom is central, and it forms a double bond with the oxygen atom. The carbon atom also has a single bond with a hydrogen atom. The oxygen atom has two lone pairs. The octet rule is satisfied for carbon and oxygen in this initial structure. However, formaldehyde exhibits resonance, meaning that electrons can delocalize and move between different positions.
The resonance structure for formaldehyde involves shifting the double bond between carbon and oxygen to create an alternative arrangement. In the resonance structure, the double bond moves to the other side of the carbon atom. This resonance structure is equally valid, as it maintains the same overall molecular arrangement and fulfills the octet rule for both carbon and oxygen. The actual structure of formaldehyde is considered to be a hybrid of these resonance structures.
The representation of resonance structures is a crucial aspect of understanding the electronic structure of molecules. It highlights the dynamic nature of electron distribution and helps to explain molecular properties and behaviors that cannot be fully captured by a single Lewis structure. In the case of formaldehyde, considering resonance structures provides a more accurate representation of the molecule's electronic configuration.