Re: When ionic compounds dissolve, why do they retain their properties?

The elemental state of chlorine is Cl₂ gas and the elemental state of sodium is a metal (neutral Na). Both are very reactive and do not exist in nature in these states. Chlorine is more stable as the negatively charged anion (Cl^-) and sodium is more stable as the positively charged cation (Na⁺). These ions have much different chemical properties than the elemental states. Together the chloride anion and sodium cation form the ionic compound NaCl, which is ordinary table salt. When the salt is dissolved in water, the sodium ions and the chloride ions are separated from each other by water molecules. In this situation, these ions have no way to be converted to their elemental states. Converting these ions to their neutral states would require transferring an electron from the chloride anion to the sodium cation. This can only occur with an input of energy because the elemental states are energetically less stable. If that energy is in fact applied, in a process called electrolysis, neutral sodium and chlorine can be created (and chlorine gas will bubble out of the solution). This is how chlorine gas in produced industrially. But without that input of energy, the ions will be unaffected.

Finally, to answer your last question, salty water tastes the same as solid table salt because they both form the same solution of sodium cations and chlorine anions in the water (saliva) in your mouth.