Question

Select the correct statement(s) with respect to the p$\pi$ - d$\pi$ dative bond.

• A. In $(P{h}_{3}Si{)}_{2}O$, the Si-O-Si group is nearly linear
• B. Silanols such as $(C{H}_3{)}_{3}SiOH$ are stronger protonic acids then their carbon analogs
• C. Trisilyl phosphine $P(Si{H}_3{)}_3$ is planar
• D. $Cl{O}_4^{-}$ does not polymerise at all

Answer 1

Answer: (A), (B), (D)

The correct options are
A In $(P{h}_{3}Si{)}_{2}O$, the Si-O-Si group is nearly linear
B Silanols such as $(C{H}_3{)}_{3}SiOH$ are stronger protonic acids then their carbon analogs
D $Cl{O}_4^{-}$ does not polymerise at all

A) Steric repulsions of bulkier groups and p$\pi$ - d$\pi$ dative bonding favour for a linear Si-O-Si group.

B) Due to stabilization of the conjugate base anion by p$\pi$ - d$\pi$ dative bonding between O - Si.

c) It is pyramidal because p$\pi$ - d$\pi$ bonding is not effective due to bigger size of phosphorus atom.

d) Most effective p$\pi$ - d$\pi$ overlapping due to small size of chlorine.