Concept:The standard enthalpy of hydration (\( \Delta H_{\text{hyd}} \)) is the enthalpy change when one mole of gaseous ions dissolves in sufficient water to give an infinitely dilute solution.
Formula:$$ H^+_{(g)} + H_2O_{(l)} \rightarrow H_3O^+_{(aq)} $$
Solution:- The gaseous hydrogen ion (\( H^+ \)) is extremely small and possesses a very high charge density.
- When it interacts with the polar water molecules, strong ion-dipole forces are established, releasing a massive amount of heat energy.
- Experimentally, the hydration energy of the \( H^+ \) ion is exceptionally high and is recorded as \( -1075 \text{ kJ/mol} \).
Why other options are incorrect:The other numerical values do not match the measured standard enthalpy of hydration for the proton. They are incorrect distractor values.
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