Consider limiting the simplest hydrocarbon molecule of methane.Its formula is as follows: CH4.The spatial model of the molecule represents a tetrahedron.Carbon atom forms four hydrogen atoms are exactly the same length and power connection.In them, according to the above example, involving 3 - p electron and 1 S - electron orbitals of which was exactly the same as the other three orbitals of the electrons as a result of hybridization occurred .This type is called hybridization sp ^ 3 hybridization.It is inherent in all saturated hydrocarbons.
But the simplest representative of unsaturated hydrocarbons - ethylene.Its formula is as follows: C2H4.What type of hybridization of carbon inherent in the molecule of the substance?As a result, it formed a three orbital a
symmetric "eights" lying in the same plane at an angle of 0 ~ 120 to each other.They formed 1 - S 2 - P electron.Last 3rd R - electron is not modified his orbital, that is, she stayed in a regular "eight".This type is called hybridization sp ^ 2 hybridization.
How bonds are formed in the ethylene molecule?Two hybridized orbitals of each atom interacted with two hydrogen atoms.Third hybridized orbital formed a bond with the same orbital of the other carbon atoms.The remaining P - orbital?They 'were attracted "to each other on both sides of the plane of the molecule.Between the carbon atoms form a double bond.That atom with a "double" bond is inherent in sp ^ 2 hybridization.
And what happens in the molecule acetylene or Etina?Its formula is as follows: C2H2.Each carbon atom hybridization exposed only two electrons: 1 and 1 --S - R. The remaining two retained orbital in a "correct eights" overlap "in the plane of the molecule and on both sides of it.That's why this type of hybridization is called sp - hybridization.It is inherent in the atoms with a triple bond.