1.2 Tetravalency and hybridization of carbon atom

  General Organic Chemistry

    1.0 Introduction
    2.0 Classification of organic compounds
    3.0 Homologous series
    4.0 Nomenclature of hydrocarbons
    5.0 Nomenclature of compounds containing halogens and nitro groups
    6.0 Nomenclature of compounds with functional groups named as suffixes
    7.0 Nomenclature of aromatic compounds
    8.0 Radicofunctional naming
    9.0 Organic reactions
    10.0 Electrophiles
    11.0 Nucleophiles
    12.0 Breaking and forming of bonds
    13.0 Reaction intermediates
    14.0 Electron displacement effects
    15.0 Inductive effects
    16.0 Hyperconjugation
    17.0 Resonance
    18.0 Mesomeric effect
    19.0 Electromeric effect
    20.0 Inductomeric effect
    21.0 Steric inhibition of resonance
    22.0 Ortho effect

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1.2 Tetravalency and hybridization of carbon atom

Tetravalency of carbon

Carbon atom present in organic compounds always shows tetravalency.

A carbon atom can attach to other atoms by single, double or triple bonds.

Carbon atom in ground state: $\mathop {\boxed \uparrow }\limits^{2s} \mathop {\boxed \uparrow \boxed \uparrow \boxed{}}\limits^{2p} $

Carbon atom in excited state: $\underbrace {\boxed \uparrow \quad \boxed \uparrow \boxed \uparrow \boxed \uparrow }_{s{p^3}{\text{ hybridisation}}}$

The process of mixing of atomic orbitals to form a set of new equivalent orbitals is termed as hybridisation.

Thus, carbon atom can combine with four $H-$ atoms, all the four $C-H$ bonds are identical and all four bonds are not present in the same plane.

Types of hybridization of $C-$ atom

Hybridization	Participating orbitals	Number of equivalent orbitals formed	Unhybridised orbitals	Structure	Bond angle	Examples
$s{p^3}$	one $s$ and three $p$	$4$	$0$	Tetrahedral	$109^\circ 28'$	Ethane, methane
$s{p^2}$	one $s$ and two $p$	$3$	$1\ (p_s)$	Trigonal planar	$120^\circ $	Ethene, propene
$sp$	one $s$ and one $p$	$2$	$2\ (p_x,p_y)$	Linear	$180^\circ $	Ethyne, Propyne