Concept:The hybridization of an atom can be quickly determined by its steric number (the sum of sigma bonds and lone pairs attached to it).
Formula:$$ \text{Steric Number} = 3 \sigma \text{ bonds} + 0 \text{ lone pairs} = 3 $$
Solution:- In ethene, each Carbon atom forms a double bond with the other Carbon and single bonds with two Hydrogen atoms.
- A double bond consists of one sigma bond and one pi bond. Therefore, each Carbon has exactly 3 sigma bonding domains.
- A steric number of 3 dictates the mixing of one s-orbital and two p-orbitals, resulting in \( \text{sp}^2 \) hybridization.
Why other options are incorrect:- Option B: Occurs when carbon has triple bonds or two double bonds (steric number 2).
- Option C: Occurs when carbon has four single bonds (steric number 4).
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