Electical conductivity

Pure alkane, pure alkene, pure alkanol, pure alkanal and pure alkanoic acid CANNOT conduct electricity.

When dissolved in water, only the solution of alkanoic acid can conduct electricity. This is because only alkanoic acid can be ionized in water to give alkanoate and hydrogen ions.
RCOOH(aq) ≒ RCOO-(aq) + H+(aq)
All the other four compounds CANNOT be ionized in water.
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