In which of the following molecules,sigma bonds formed by the overlap of sp3d and p-orbitals are absentA)pcl5B)clF3C)sbcl5D)HclO4

To determine which of the given molecules lacks sigma bonds formed by the overlap of sp³d and p-orbitals, we need to analyze the molecular structures and hybridization of each compound. Let's break down each option one by one.

PCl5

PCl5, or phosphorus pentachloride, has a trigonal bipyramidal geometry. The phosphorus atom undergoes sp³d hybridization, which allows it to form five sigma bonds with chlorine atoms. Therefore, PCl5 does contain sigma bonds formed by the overlap of sp³d and p-orbitals.

ClF3

Chlorine trifluoride (ClF3) has a T-shaped molecular geometry. In this case, the chlorine atom also undergoes sp³d hybridization to form three sigma bonds with fluorine atoms. Thus, ClF3 contains sigma bonds formed by the overlap of sp³d and p-orbitals.

SbCl5

Antimony pentachloride (SbCl5) is similar to PCl5 in that it has a trigonal bipyramidal structure. The antimony atom undergoes sp³d hybridization, forming five sigma bonds with chlorine atoms. Therefore, SbCl5 also contains sigma bonds formed by the overlap of sp³d and p-orbitals.

HClO4

Now, let’s look at perchloric acid (HClO4). In this molecule, the chlorine atom is bonded to four oxygen atoms and one hydrogen atom. The hybridization of chlorine in HClO4 is typically considered to be sp³, as it forms four sigma bonds with the oxygen atoms and one with hydrogen. However, it does not involve sp³d hybridization since there is no trigonal bipyramidal geometry present. Instead, the bonding involves p-orbitals for the double bonds with oxygen. Therefore, HClO4 does not have sigma bonds formed by the overlap of sp³d and p-orbitals.

Final Analysis

Based on this analysis, the molecule that does not have sigma bonds formed by the overlap of sp³d and p-orbitals is:

• HClO4

This conclusion stems from the fact that HClO4 does not exhibit the necessary hybridization that involves sp³d orbitals, unlike the other options provided.