Which atom in each pair would you expect to be the central atom in a Lewis structure?
(b) C vs. O

Verified step by step guidance

1. Identify the general rule for selecting a central atom in a Lewis structure: The central atom is typically the least electronegative element, as it is more likely to share its electrons and form bonds with surrounding atoms.
2. Compare the electronegativities of carbon (C) and oxygen (O). Carbon has an electronegativity of approximately 2.5, while oxygen has a higher electronegativity of approximately 3.5.
3. Since carbon is less electronegative than oxygen, it is more likely to serve as the central atom in a Lewis structure.
4. Consider the bonding capacity of each atom. Carbon typically forms four bonds (due to its four valence electrons), making it well-suited to act as a central atom. Oxygen, on the other hand, typically forms two bonds.
5. Conclude that carbon (C) is the preferred central atom in this pair when constructing a Lewis structure, based on its lower electronegativity and higher bonding capacity.

Key Concepts

Lewis Structures

Lewis structures are diagrams that represent the bonding between atoms in a molecule and the lone pairs of electrons that may exist. They help visualize the arrangement of electrons and the connectivity of atoms, which is crucial for predicting molecular geometry and reactivity.

Central Atom

The central atom in a Lewis structure is typically the atom that can form the most bonds or has the highest valence. It is usually the least electronegative element in a molecule, as it can effectively bond with surrounding atoms, allowing for a stable structure.

Electronegativity

Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond. In the context of determining the central atom, the atom with lower electronegativity is often preferred, as it is more likely to share its electrons and form bonds with other atoms.