What orbitals does phosphorus use to form five bonds in PCl5?

Phosphorus pentachloride has a trigonal bipyramidal shape with five P–Cl bonds. Phosphorus uses its 3s orbital, three 3p orbitals, and one 3d orbital to form five sp3d hybrid orbitals. These five sp3d hybrid orbitals are directly involved in bonding with the five chlorine atoms.

How does sp3d2 hybridization explain the octahedral structure of SF6?

Sulfur hexafluoride exhibits sp3d2 hybridization, forming six equivalent hybrid orbitals arranged in an octahedral geometry. The sulfur atom combines its 3s orbital, three 3p orbitals, and two 3d orbitals to create six sp3d2 hybrid orbitals. Each hybrid orbital forms a sulfur–fluorine bond directed toward a corner of the octahedron.

Why can't pi bonds rotate around the internuclear axis?

Pi bonds form from the side-on overlap of two p orbitals, creating electron density on opposite sides of the internuclear axis. This perpendicular arrangement prevents rotation around the bond axis. Pi bonds only form in double and triple bonds when a sigma bond already exists between two atoms.

What is the bonding composition of the double bond in ethene?

Ethene contains sp2 hybridized carbons that form one carbon–carbon sigma bond through overlap of sp2 hybrid orbitals. The unhybridized 2p orbitals on each carbon overlap sideways to produce a pi bond. Therefore, the ethene double bond consists of one sigma and one pi bond.

How does sp hybridization produce the linear geometry of ethyne?

In ethyne, both carbon atoms undergo sp hybridization, producing two sp orbitals and leaving two unhybridized 2p orbitals. One sp orbital forms a carbon–carbon sigma bond, while the other forms a carbon–hydrogen sigma bond. The two perpendicular 2p orbitals overlap sideways to form two pi bonds, creating a triple bond.

Which atoms can exhibit sp3d and sp3d2 hybridization?

Only atoms with d orbitals in their valence subshells can exhibit sp3d and sp3d2 hybridization. This excludes atoms in the first and second periods. Examples include phosphorus in PCl6−, iodine in interhalogens like IF5, and xenon in XeF4, all of which have accessible d orbitals for bonding.

How many sigma and pi bonds form in ethyne?

Ethyne contains one sigma bond between the two carbon atoms and one sigma bond between each carbon and hydrogen atom, totaling three sigma bonds. Additionally, two pi bonds form from the sideways overlap of unhybridized 2p orbitals. The triple bond consists of one sigma and two pi bonds between carbons.

10.7

Hybridization of Atomic Orbitals II

37.7K views03:35 min

The trigonal bipyramidal, octahedral, and other molecular shapes can be explained by assuming the participation of 3d orbitals in the process of hybridization.

The phosphorus pentachloride molecule has a trigonal bipyramidal shape, and it contains 5 valence electrons. Phosphorus uses the 3s orbital, the three 3p orbitals, and one of the 3d orbitals to form five sp³d hybrid orbitals that are involved in the phosphorus–chlorine bonds.

Sulfur hexafluoride has an octahedral structure and it contains 6 valence electrons. The 3s orbital, the three 3p orbitals, and two of the 3d orbitals on sulfur form six equivalent sp³d² hybrid orbitals. These six sp³d² orbitals form an octahedral structure around sulfur and participate in the formation of sulfur–fluorine bonds.

The concept of hybridization also provides an explanation for the formation of multiple bonds. The side-on overlap of two p orbitals gives rise to a π bond.

However, a π-bond can only be formed in double and triple bonds when a σ bond already exists between two atoms. Because the π bond exists on opposite sides of the internuclear axis, π bonds are unable to rotate around this axis.

In the ethene molecule, both carbons exhibit sp² hybridization. The mixing of one s orbital and two p orbitals of a carbon atom produce three identical sp² hybrid orbitals, and one p orbital remains unhybridized.

The carbon–carbon σ bond is formed by the overlap of two sp² hybrid orbitals, one on each carbon atom.

The two carbon–hydrogen σ bonds on each carbon are formed by the overlap of two sp² hybrid orbitals with the 1s orbitals on the hydrogen atom. Thus, five σ bonds are formed in the ethene molecule.

The unhybridized 2p orbitals on the carbons overlap sideways with each other to produce a π bond. All six atoms lie in the same plane, and therefore 2p orbitals can overlap effectively.

Thus, the double bond in ethene consists of one σ and one π bond.

The triple bonds and the linear geometry of ethyne can be explained using sp hybridization. The 2s and 2p orbitals of both carbon atoms undergo hybridization to produce two sp orbitals each, and two p orbitals remain unhybridized.

One of the sp-orbitals forms a σ bond with the other carbon atom, whereas the remaining sp orbital forms a σ bond with a hydrogen atom. The two unhybridized 2p orbitals are perpendicular and intersect at the principal axis of the sp hybrid orbitals.

These 2p orbitals overlap sideways with the 2p orbitals of the other carbon atom resulting in the formation of two π bonds. Therefore, the triple bond in ethyne consists of one σ bond and two π bonds between the two carbon atoms.