Given the molecule $C_2{H}_4$ (ethene), label the hybridization of each carbon atom.

• A. Each carbon atom is $\mathrm{sp}$ hybridized.
• B. Each carbon atom is ${\mathrm{sp}}^2$ hybridized.
• C. Each carbon atom is ${\mathrm{sp}}^3$ hybridized.
• D. One carbon is $\mathrm{sp}$ and the other is ${\mathrm{sp}}^3$ hybridized.

Answer: (B)

Verified step by step guidance

1. Identify the molecular formula given: C2H4, which corresponds to ethene, a molecule with a carbon-carbon double bond.
2. Recall that the hybridization of a carbon atom depends on the number of sigma bonds and lone pairs around it. For ethene, each carbon forms three sigma bonds: two with hydrogen atoms and one with the other carbon atom.
3. Since each carbon forms three sigma bonds and has no lone pairs, the hybridization corresponds to sp2. This involves mixing one s orbital and two p orbitals to form three sp2 hybrid orbitals.
4. The remaining unhybridized p orbital on each carbon overlaps side-by-side to form the pi bond of the double bond.
5. Therefore, label each carbon atom in ethene as sp2 hybridized, reflecting the trigonal planar geometry around each carbon.