Why is the H-H Bond Dissociation Enthalpy so high? [closed]








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"The H-H Bond Dissociation Enthalpy is the highest for a single bond between 2 atoms of any element."




The bond dissociation enthalpy is the energy needed to break one mole of the bond to give separated atoms - everything being in the gas state.


For covalent bonds, bond energies and bondlengths depend on many factors: 


* electron afinities,
* **sizes of atoms involved in the bond**,
* differences in their electronegativity,
* **and the overall structure of the molecule**.


There is a general trend in that the **shorter the bondlength**, the higher the **bond energy**. 


Hydrogen has a relatively **small atom** and **short bondlength** hence very strong strong attractions between the atoms which will consenquently increase its bond dissociation ethalpy.


Credits


1. [Bond enthalpy (Bond energy)](http://www.chemguide.co.uk/physical/energetics/bondenthalpies.html)
2. Inorganic chemistry bond enthalpy of Hydrogen][2](http://www.askiitians.com/forums/Inorganic-Chemistry/20/7117/hydrogen.htm)


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