What is the hybridization of the carbon atom in the methyl cation CH3+?
The correct answer and explanation is:
The hybridization of the carbon atom in the methyl cation (CH₃⁺) is sp².
Explanation:
The methyl cation (CH₃⁺) is formed when a neutral methane molecule (CH₄) loses one electron, resulting in a positively charged carbon atom. In CH₄, the carbon atom is sp³ hybridized, as it forms four bonds with hydrogen atoms using four sp³ hybrid orbitals. However, in the methyl cation (CH₃⁺), the carbon atom loses one of its electrons, leaving it with only three valence electrons. This leads to a situation where there are only three bonds (one with each hydrogen atom), and the carbon atom is positively charged.
To understand the hybridization of the carbon atom in CH₃⁺, we need to consider its bonding and electron configuration. The carbon atom in CH₃⁺ still forms three sigma bonds with the hydrogen atoms. However, with only three bonding electrons and no lone pairs of electrons, the carbon atom must adopt a geometry that accommodates three bonds, which suggests that the carbon atom undergoes sp² hybridization.
In sp² hybridization, one s orbital and two p orbitals mix to form three equivalent sp² hybrid orbitals. These orbitals are arranged in a trigonal planar geometry with 120° bond angles. The third p orbital remains unhybridized and is empty, which corresponds to the missing electron in the cationic species. The three sp² hybrid orbitals form the sigma bonds with the three hydrogen atoms.
Since there is no lone pair of electrons on the carbon atom and it is positively charged, the sp² hybridization is energetically favorable. The trigonal planar geometry is also consistent with the observed bond angles in CH₃⁺, which are approximately 120°. Therefore, the carbon atom in the methyl cation is sp² hybridized.