Wed September 05, 2012 By: Rounak Singh
In page no. 105 of ncert underhead topic Bond Enthalpy where its written

My question is, the value of dissociation enthalpy changes from 502kJ/mol to 427kJ/mol in water molecule.The change is due to some change in chemical environment as stated but according to you Sir , the change is because when first O-H bond breaks the second bond gets weaken. Is my interpretation correct? Please explain the ncert paragraph in a little less complicated way. Thankyou Sir.

Expert Reply
Mon September 17, 2012
Yes you are correct .Due to some chemical changes the difference in energy obtained.
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