How do you determine the correct Lewis structure for a molecule?

[CleoVosbur]

I'm struggling with drawing Lewis structures, especially when deciding on lone pairs and bonding. Can someone explain the steps or share tips?

 

[DeeReich70]

To determine the correct Lewis structure for a molecule, follow these steps:

1. Count total valence electrons for all atoms in the molecule.
2. Determine the central atom (usually the least electronegative, except hydrogen).
3. Draw single bonds between the central atom and surrounding atoms.
4. Distribute remaining electrons to satisfy the octet rule (or duet for hydrogen).
5. Form double or triple bonds if needed to give all atoms a full octet.
6. Check total electrons to ensure they match your count.
7. Consider formal charges—the most stable structure has formal charges closest to zero.

 

[danisjohn]

To determine a molecule's Lewis structure, first count the valence electrons, then place the least electronegative atom in the center. Draw single bonds, distribute remaining electrons as lone pairs, and adjust bonds to fulfill the octet rule. Check formal charges, and consider resonance structures if necessary.

 

[Grace]

The least electronegative atom should be positioned in the center of a molecule after counting the valence electrons to determine its Lewis structure. To satisfy the octet rule, draw single bonds, distribute the remaining electrons as lone pairs, and modify bonds. Verify formal charges and, if needed, take resonance structures into account.