SP³ HYBRID ORBITALS AND THE STRUCTURE OF METHANE

The methane  molecule of hydrogen bonding with tetravalent atoms. Carbon have the 4 valence electron. A methane molecule (2S²2P²) and forms four bonds. Because carbon used 2 kinds of C-H bonds. All 4  C-H bonds in methane are identical and spatially oriented corner of tetrahedron.

  Linus pauling, showed mathematically one  s orbital and three p orbitals on atom to combine hybrized, to form 4 equivalent atomic orbitals with tedrahedral orientation, this oriented orbitals called Sp³ hybridized. The superscript three in the name sp³ how many each types of atomic orbitals combine to form the hybrid, not how many electrons occupied it.

four sp³ hybrids orbitals corner of a tedrahedron formed by combination of s orbitals and 3 p orbitals. The sp³ hybrids has two lobes and unsymmetrical nucleus giving them directly and allows them forms strong bonds when they overlapping orbitals from another atoms.

          This hybridization explains carbon forms 4 equivalent tetrahedral bonds. The shapes of the hybrid orbitals suggests the answer, when S orbital hybridized with 3 P orbitals, the results of sp³ hybrid orbitals unsymmetrical about that nucleus. One of the 2 lobes is bigger than the other, the overlap more effectively with orbitals from another atom to form a bond. As results sp³ hybrids orbitals from stronger bonds than unhybridized s or p orbitals.

                           This asymmetry of orbitals 2 lobes of p orbitals have different type of algebraic signs, + and - in the wave function. When a p orbitals hybrized with s orbital, the positive p lobs adds to the s orbitals but negative p lobes subtract from the s orbitals. The positively p lobes adds to the s orbital but negative p lobe subtract from the s orbitals. This orbitals unsymmetrical nucleus and strongly oriented in only one direction.

               When four identical sp³ hybrids orbitals of a carbon atom overlapping with 1s orbitals of the hydrogen atom. The 4 identically C-H bonds are formed and methane results. Each C-H bonds in methane have strength 439kj/mol and length of 109pm. The four bonds has a specific geometry, can define a property called bond angle. The angle formed by each H-C-H bond is 109.5⁰, this is called tetrahedral angle. CH4 has structure below.