Question

Assertion :$S{O}_3$ has a planar structure. Reason: $S$ atom in $S{O}_3$ is $s{p}^{2}d$ hybridized.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is C Assertion is correct but Reason is incorrect

Sulfur trioxide is regarded as an anhydride of sulfuric acid ($H_{2}S{O}_4$). $S{O}_3$ has a trigonal planar structure with bond angle ${120}^o$. The representation of $S{O}_3$ molecule is shown. In the gas phase, $S{O}_3$ molecule is a triangular planar involving $s{p}^2$ hybridization of the $S$ atom.

There are three sigma bonds formed by $s{p}^2-p$ overlap and three $\pi$ bonds, one by p( $\pi$ )-p($\pi$) overlap and two by $p$($\pi$)-$d$($\pi$) overlap. $O-S-O$ bond angles is ${120}^o$.

Thus, option $C$ is correct.