Question

How is water a good conductor of electricity? My ohmmeter indicates a lot of resistance in a bucket of water, yet I can get shocked a lot easier with the help of H2O.

Asked by: Robert Pope

 Answer

Water itself is not a conductor of electricity. In order for a substance to carry charge, two conditions must first be met:

  1. There must be charged particles within the substance (either ions or electrons) and
  2. These particles must be free to move It is true that in water (H2O) the discrete molecules are free to move, however, they carry no charge.
The only reason water can sometimes conduct electricity is because of the minerals (metallic solids) already present in the water.

Answered by: Shaun Gladman, Student BHS


Partially right but: Water itself contains 1*10-7 mol/Liter positivly charged H+ and the same amount of negativly charged HO- (ph 7) leading to a conductivity of aprocimatly 0,055 µSiemens/cm (18,2 MOhm )for pure Water at 25 °C (compared with rainwater 35 - 100 µSiemens/cm dependent on Air Polution, River (Rhein Germany ) 300 - 745 µSiemens/cm ,Sea 42 000µSiemens/cm

The high conductivity of salty water are the Salt-ions but water has in any case an amount of ions

Answered by: Ralf Biehl, Ph.D Physics, University of Mainz, Institut für Physik


The primary factor at play as to why it is easier to get shocked when water is involved is that water, being a liquid, spreads over the surface of and into the nooks and crannies of your skin much better than contact with a solid would, thus increasing the surface exposure of your skin to the electric shock.

Answered by: Howie Soucek


Another phenomena that can happen once you try to expose water to a high electric potential is that it starts ionizing, i.e. you start creating ions in the water just from the strong electric field. Then you might end up with an ion trail being created, very much like the one created in the air during lightning, where the conductivity becomes very high. This trail becomes the passage for the current with almost no resistance.

In any case avoid lightning, and electricity around wet things.

Answered by: Anton Skorucak, PhysLink.com

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