Methane valence bond structure

It may be that it is necessary in compounds containing tctravalent carbon atoms, to take into account the resonance with valence bond structures in which carbon is in the divalent, ue. state. If this be so, then for methane it is necessary to consider the resonance between the orms H H H H... 

Fig. 1.3. Valence bond structural representation of methane resulting from overlap of H Is orbitals with four equivalent sp orbitals of carbon.

The structural features of methane ethane and propane are summarrzed rn Ergure 2 7 All of the carbon atoms have four bonds all of the bonds are srngle bonds and the bond angles are close to tetrahedral In the next sectron we 11 see how to adapt the valence bond model to accommodate the observed structures... 

How does valence bond theory describe the electronic structure of a polyatomic molecule, and how does it account for molecular shape Let s look, for example, at a simple tetrahedral molecule such as methane, CH4. There are several problems to be dealt with. 

The orbitals of methane, CH4, and those of the related fragments CH3, CH2, and CH can be described using the molecular orbital method, as we have done for all the systems studied so far in this book. But the valence-bond approach, introduced by L. Pauling, can also be used this is perhaps the simplest way to establish an initial relationship between the electronic structures of organic and inorganic fragments. 

Stable than planar methane. The tetrahedral structure involves all eight valence electrons in C-H bonding, while the planar form uses only six. 

Atomic Structure The Nucleus Atomic Structure Orbitals 4 Atomic Structure Electron Configurations 6 Development of Chemical Bonding Theory 7 The Nature of Chemical Bonds Valence Bond Theory sp Hybrid Orbitals and the Structure of Methane 12 sp Hybrid Orbitals and the Structure of Ethane 13 sp2 Hybrid Orbitals and the Structure of Ethylene 14 sp Hybrid Orbitals and the Structure of Acetylene 17 Hybridization of Nitrogen, Oxygen, Phosphorus, and Sulfur 18 The Nature of Chemical Bonds Molecular Orbital Theory 20 Drawing Chemical Structures 21 Summary 24... 

This Lewis structure shows methane, the simplest organic compound. The carbon atom has four valence electrons, and it obtains four more electrons by forming four covalent bonds with the four hydrogen atoms. 

Customarily, carbon completes its valence-shell octet by sharing electrons with other atoms. In compounds with shared electron bonds (or covalent bonds) such as methane, ethane, or tetrafluoromethane, each of the bonded atoms including carbon has its valence shell filled, as shown in the following electron-pair or Lewis6 structures ... 

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