Question

Which of the following statement(s) is/are correct?
As the s-character of a hybrid orbital decreases,
(I) the bond angle decreases
(II) the bond strength increases
(III) the bond length increases
(IV) the size of orbital increases

• A. (I), (II) and (IV)
• B. (I), (III) and (IV)
• C. (I) and (II)
• D. (I), (II), (III) and (IV)

Answer 1

Answer: (B)

(I), (III) and (IV)

The statements (I), (III) and (IV) are correct.
As the s-character of a hybrid orbital decreases,
(I) the bond angle decreases. The bond angles for sp, $s{p}^2$ and $s{p}^3$ hybrid orbitals are ${180}^o$, ${120}^o$ and ${109}^o$ respectively.
(II) the bond strength decreases. Triple bond (sp hybridisation) is stronger than double bond ($s{p}^2$ hybridisation) which in turn is stronger than single bond ($s{p}^3$ hybridisation).
(III) the bond length increases. Triple bond (sp hybridisation) is shorter than double bond ($s{p}^2$ hybridisation) which in turn is shorter than single bond ($s{p}^3$ hybridisation).
(IV) the size of orbital increases. s orbital is smaller than p orbital. Hence, sp hybrid orbitals are smaller than $s{p}^2$ hybrid orbitals which in turn are smaller than $s{p}^3$ hybrid orbitals.