Question

How would you account for the following:
(i) H2S is more acidic than H2O.
(ii) The N—O bond in NO2- is shorter than the N—O bond in NO3- .
(iii) Both O2 and F2 stabilise high oxidation states but the ability of oxygen to stablise the higher oxidation state exceeds that of fluorine.

Answer 1

(i) This is because bond dissociation enthalpy of H—* bond is lower than that of H—O bond.
(ii) This is because two bonds share a double bond in the resonance hybrid structure of NO2– while three bonds share a double bond in the resonance hybrid structure of NO3– . This is because NO2– has bond order 1.5 while NO3–has bond order 1.33.

(iii) This is due to tendency of oxygen to form multiple bonds with metal atom.