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for hybridisations at school level only


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What is hybridisation: 

W hat is hy b ridisation Hybridization is the concept of mixing atomic orbital to form new hybrid orbital suitable for the qualitative description of atomic bonding properties. Hybridized orbital are very useful in the explanation of the shape of orbital for molecules. It is an integral part of valence bond theory. Although sometimes taught together with the valence shell electron-pair repulsion (VSEPR) theory, valence bond and hybridization are in fact not related to the VSEPR model.

types of hybridization: 

types of hybridization sp( s+p ) sp 2 ( s+p (2)) sp 3 ( s+p (3)) dsp 2 ( d+s+p (2)) sp 3 d( s+p (3)+d) sp 3 d 2 ( s+p (3)+d(2)) d 2 sp 3 (d(2)+s+p(3))

Sp hybridization: 

Sp hybridization It is formed by mixing of s and p orbitals or b/w 2 p(z). It has 50% s-character and 50% p-character. A single sp -hybrid has most of its electron density on one side, with a minor and more spherical lobe on the other side. This minor lobe is centered on the central atom.

Sp hybridization in acetylene: 

Sp hybridization in acetylene In this model, the 2 s orbital mixes with only one of the three p -orbitals resulting in two sp orbitals and two remaining unchanged p orbitals. The chemical bonding in acetylene ( ethyne ) (C 2 H 2 ) consists of sp – sp overlap between the two carbon atoms forming a σ bond and two additional π bonds formed by p – p overlap. Each carbon also bonds to hydrogen in a sigma s – sp overlap at 180° angles.

sp2 hybridization: 

sp 2 hybridization The process of hybridization in which one s-orbital and two p-orbital overlap to produce three hybrid orbitals is known as sp 2 - HYBRIDIZATION or TRIGONAL HYBRIDIZATION. These orbital are coplanar and directed towards the corners of an equilateral triangle at an angle of 120 o from each other.

sp2 hybridization in ethene: 

sp 2 hybridization in ethene In ethene , each carbon atom is Sp 2 -hybridized. In this way six Sp 2 -orbitals are generated (three for each carbon atom). One Sp 2 -orbital of each carbon atom by overlapping forms a sigma bond between carbon atoms. Remaining two Sp 2 -orbital of each atom overlap with 1s-orbital of hydrogen atom to produce four sigma bonds. P(z) un-hybrid orbital of each carbon atom by the parallel overlapping form a pi-bond between two carbon atoms.

sp3 hybridization: 

sp 3 hybridization The process of hybridization in which one s-orbital and three p-orbital overlap to produce four hybrid orbitals is known as sp 3 - HYBRIDIZATION or TETRAHEDRAL HYBRIDIZATION. These orbital are directed towards the corners of a pyramid at an angle of 109.5 o from each other.

sp3 hybridization in ethAne: 

sp 3 hybridization in ethAne In ethane each C-atom is Sp 3 -hybridized containing four Sp 3 -hybrid orbital. One s-orbital and three p-orbital (px, py, pz) undergo Sp 3 -hybridization to produce four Sp 3 -hybrid orbitals for each carbon    atom. Out of four Sp 3 -hybrid orbital one Sp 3 -hybrid orbital of one C-atom overlaps with one s-orbital of H-atom to produce three sigma bond and the last overlaps with one Sp 3 -orbital of other C-atom to produce a sigma bond between two C-atoms.

dsp2 hybridization: 

dsp 2 hybridization dsp 2 type of hybridization is also known particularly in case of transition metal ions. The orbitals involved in this type of Hybridization are d x 2 - y 2 , s and two p. The four dsp 2 hybrid orbitals adopt square planar geometry. Ex:- [Ni(CN) 4 ] 2-

sp3D hybridization: 

sp 3 D hybridization This Hybridization involves the mixing of one s, three p and one d-orbital. These five orbitals hybridize to form five sp 3 d-hybrid orbitals. These hybrid orbitals point towards the corners of a trigonal bipyramidal geometry. In this case, the three orbitals forming a plane are directed towards the corners of an equilateral triangle while the other two are perpendicular to the plane of the triangle lying above and below it.

sp3D2 hybridization: 

sp 3 D 2 hybridization In this case, one s, three p and two d-orbitals get hybridized to form six sp 3 d 2 hybrid orbitals which adopt octahedral arrangement.

sp3D2 hybridization IN SF6 molecule : 

sp 3 D 2 hybridization IN SF 6 molecule The geometry of SF 6 molecule can be explained on the basis of sp 3 d 2 Hybridization. In SF 6 the central sulphur atom has the ground state configuration, 3s 2 3p 4 . To account for the hexavalency in SF 6 one electron each from 3s and 3p orbitals is promoted to 3d orbitals . These six orbitals get hybridised to form six sp 3 d 2 hybrid orbitals. Each of these sp 3 d 2 hybrid orbitals overlaps with 2p orbital of fluorine to form S-F bond. Thus, SF 6 molecule has octahedral structure as shown in The dotted electrons represent electrons from F-atoms.

Slide 16: 

No. of electron Groups Hybridization Geometry Shape 2 sp Linear 3 sp 2 Triganol Planar 4 sp 3 Tetrahedral

Slide 17: 

5 dsp 3 Triganol bipyramidal 6 d 2 sp 3 Octahedral

Slide 18: 

Presented by adrita kundu xi-a