On one hand, the ionic bond in sodium chloride is pretty hard to break, reflected in the difficulty of extracting elemental sodium from table salt.
On the other hand, water dissolves salt easily, breaking the ionic bond.
What is going on? Probably something along the lines of, the hole of the Na+ ion gets delocalized over the Na(H2O)n complex cation, and getting to that complex from solid NaCl is not difficult. Filling the hole, going from an ion to neutral, whether as an atom or complex, is difficult.
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