Which combination correctly describes an sp3 hybridized carbon?

Which combination correctly describes an sp3 hybridized carbon?

• A. Linear geometry; 180 degrees
• B. Tetrahedral geometry; 109.5 degrees
• C. Trigonal planar geometry; 120 degrees
• D. Trigonal planar geometry; 109.5 degrees

Answer: (B)

sp3 hybridization involves mixing one s orbital with three p orbitals to create four equivalent sp3 orbitals. These four orbitals point toward the corners of a tetrahedron, so the geometry around the carbon is tetrahedral and the ideal bond angles are about 109.5 degrees. This is why an sp3-hybridized carbon typically forms four sigma bonds in a tetrahedral arrangement, like in methane. Linear geometry with 180 degrees comes from sp hybridization (two electron regions giving a straight line). Trigonal planar geometry with 120 degrees comes from sp2 hybridization (three electron regions in a plane). A trigonal planar arrangement with 109.5 degrees would be inconsistent, since three regions of electron density yield ~120-degree angles, not 109.5.

sp3 hybridization involves mixing one s orbital with three p orbitals to create four equivalent sp3 orbitals. These four orbitals point toward the corners of a tetrahedron, so the geometry around the carbon is tetrahedral and the ideal bond angles are about 109.5 degrees. This is why an sp3-hybridized carbon typically forms four sigma bonds in a tetrahedral arrangement, like in methane.

Linear geometry with 180 degrees comes from sp hybridization (two electron regions giving a straight line). Trigonal planar geometry with 120 degrees comes from sp2 hybridization (three electron regions in a plane). A trigonal planar arrangement with 109.5 degrees would be inconsistent, since three regions of electron density yield ~120-degree angles, not 109.5.