There is a general tendency for liquids to conduct electricity better than solids due to

There is a general tendency for liquid to conduct electricity better than solids due to free ions.

Explanation:

There is a general tendency for liquid to conduct electricity better than solids due to free ions.

Take an example of aqueous NaCl and solid NaCl.  When Nacl is dissolved in water then it will get dissociated in to ions. This state of NaCl is called aqueous state of the Nacl. In this state , the ions are free to conduct electricity.

Solid NaCl does not have free ions to conduct electricity.

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