Using Average Bond Energies to Estimate Enthalpy Changes for Reactions

Using Average Bond Energies to Estimate Enthalpy Changes for Reactions 

We can use average bond energies to estimate the enthalpy change of a reaction. For example, consider the reaction between methane and chlorine  

Estimating the Enthalpy Change of a Reaction from Bond Energies 

We find that = -113 kJ. Calculating from tabulated enthalpies of 

When we say that energy is stored in a compound, or that a compound is energy rich, we mean that the compound can undergo a reaction in which weak bonds break and strong bonds form, thereby releasing energy in the overall process. 

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