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Explain why NaCl does not conduct electricity when solid but does conduct when molten or in solution

Hello All,

I am revising past papers again and I am not sure if I answered this particular question correctly. Can anyone please give me their feedback. Thank you . Here is the question and my answer underneath.

[b]Explain why NaCl does not conduct electricity when solid but does conduct when molten or in solution[/b]

NaCl (common salt) is solid in state and solid ions or compounds don't conduct electricity. It needs to be either melted, molten or dissolved in a solution (i.e. water) first. This is because the electrons in a solid state won't be free to move to either the Cathode (-ve) or to the Anode (+ve). In a liquid state the electrons are free enough to move.

Thanks a lot

Solids DO conduct electricity under some circumstances.  For instance, all metals are conductors in the solid state.  Graphite conducts in the solid state.

There are two keys to conducting electricity.  There must be
1) charged particles
and
2) the charged particles must be free to move

In the case of any form of sodium chloride there are charged particles (the positive and negative ions).  However, in solid NaCl the charged particles are locked in place in the crystal lattice and not able to move, and thus solid NaCl does not conduct electricity.  When the NaCl melts, or dissolves in water, the crystal lattice breaks down and the charged particles are able to move, allowing electricity to be conducted.