What is the hybridization of all the atoms (other than hydrogen) in each of the following?
What are the bond angles around each atom?
c. ^-CH₃
d. ⋅CH₃

Verified step by step guidance

1. Step 1: Understand the concept of hybridization. Hybridization is the mixing of atomic orbitals to form new hybrid orbitals that are used to form bonds. The type of hybridization depends on the steric number (number of sigma bonds + lone pairs) around the atom.
2. Step 2: Analyze the structure of -CH3 (methyl anion). The carbon atom in -CH3 has three sigma bonds (to three hydrogen atoms) and one lone pair. Calculate the steric number: 3 sigma bonds + 1 lone pair = 4. A steric number of 4 corresponds to sp³ hybridization. The bond angles around an sp³ hybridized atom are approximately 109.5°.
3. Step 3: Analyze the structure of ⋅CH3 (methyl radical). The carbon atom in ⋅CH3 has three sigma bonds (to three hydrogen atoms) and one unpaired electron. Calculate the steric number: 3 sigma bonds + 0 lone pairs = 3. A steric number of 3 corresponds to sp² hybridization. The bond angles around an sp² hybridized atom are approximately 120°.
4. Step 4: Note the difference between the two species. In -CH3, the lone pair on carbon contributes to the steric number, leading to sp³ hybridization. In ⋅CH3, the unpaired electron does not contribute to the steric number, resulting in sp² hybridization.
5. Step 5: Summarize the findings. For -CH3, the carbon is sp³ hybridized with bond angles of approximately 109.5°. For ⋅CH3, the carbon is sp² hybridized with bond angles of approximately 120°.

Key Concepts

Hybridization

Hybridization is the concept of mixing atomic orbitals to form new hybrid orbitals that can accommodate the bonding requirements of an atom. In organic chemistry, common types include sp, sp2, and sp3 hybridization, which correspond to different geometries and bond angles. For example, sp3 hybridization leads to tetrahedral geometry with bond angles of approximately 109.5 degrees.

Bond Angles

Bond angles are the angles formed between two adjacent bonds at a central atom. They are influenced by the hybridization of the atom and the presence of lone pairs, which can repel bonding pairs and alter the ideal angles. Understanding bond angles is crucial for predicting molecular shapes and reactivity in organic compounds.

Molecular Geometry

Molecular geometry refers to the three-dimensional arrangement of atoms within a molecule. It is determined by the number of bonding pairs and lone pairs around a central atom, which dictate the spatial orientation of the bonds. This concept is essential for understanding the physical and chemical properties of molecules, including their reactivity and interactions.