copy of structure and bonding 3
DESCRIPTION
axes perpendicular to each other. But the newly formed sp3 hybrid orbitals consist of two lobes one big and the other small. These orbitals tend to lie as far apart in space due to mutual repulsion of the electron clouds in them. They get directed towards the four corners of a regular tetrahedron with the carbon atom in the center. Therefore this hybridisation is also called as tetrahedral hybridisation with an angle of 109.5 between the hybrid orbitals.TRANSCRIPT
Structure and Bonding
Ethene - C2H6In the formation of ethylene, each carbon atom undergoes sp2 hybridisation leaving 2pz orbital unhybridised. One of the sp2 hybridised orbital of one carbon atom overlaps axially with sp2 hybridised orbital of the other carbon atom to form a stable sigma bond (C-C). The remaining two sp2 hybrid orbitals of both carbon overlap axially with the half filled '1s' orbital of hydrogen atoms forming four C-H sigma bonds. The unhybridised orbital (2pz) of one carbon atom overlaps sidewise with the similar orbital of the other carbon atom to form a weak pi bond. Thus, in ethylene all the six atoms containing the sigma bonds lie in one plane while the pi bond is at a plane perpendicular to the plane of the six atoms.
'sp' hybridisation: if One s and one p Atomic orbitals intermix to produce two new identical orbitals, the hybridization i s said to be Sp or diagonal and the new orbitals formed are called as sP hybrid orbitals. In this type of hybridisation one '2s' and one '2px' orbitals get hybridised to form two equivalent orbitals called 'sp' hybrid orbitals. The remaining 2py and 2pz do not take part in hybridisation. The two unhybridised orbitals are directed along the 'y' and 'z' axes while the two hybridised orbitals are directed towards the 'x' axis. This hybridisation is often known as diagonal hybridisation as the two hybridised orbitals are at 180o due to mutual repulsion of their electron clouds. Each hybrid orbital has equal 's' and 'p' character.
Page 1