Electric field in water, using voltage, without electrolysis

AI Thread Summary
Creating an electric field in water using electrodes with a voltage difference of 10-15V typically results in electrolysis, evidenced by bubble formation at the electrodes. Insulated electrodes may help mitigate this issue, but achieving a significant electric field without any electrolysis is challenging. Research indicates that in very salty water, such as in the North Sea, electrolysis can be avoided at voltages below 1.7V. Some experiments suggest that low voltages, around 0.2V, can create electric fields without causing electrolysis. Overall, while it is theoretically possible to create an electric field in water without electrolysis, practical limitations exist at higher voltages.
sina_mech
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Hi!

Can we create electric field in water, using electrodes (say 10-15V of voltage difference), without having electrolysis or arc in water? (the water can be salty). I just read that insulated electrodes can be used. but I'm not sure.

PS: Sorry if the question sounds silly. My field of study is so far from these topics :)

Thank you :)
 
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Yes. In an introductory laboratory course, many years ago, I used an electric field mapping apparatus which consisted of a shallow tray of water with electrodes of various shapes. I don't remember what the voltage was. As I recall, we did have some small bubbles forming at the electrodes, but they didn't cause any problems.
 
@jtbell Thank you for your reply. Actually those small bubbles matter. I'd like to know if there is a way to have the field without having the bubbles (which are the result of electrolysis).
 
Any suggestion? :)
 
sina_mech said:
Can we create electric field in water, using electrodes (say 10-15V of voltage difference), without having electrolysis or arc in water?
Some colleagues of mine did extensive measurements on oil pipes under water, and they concluded that the voltage had to be very low. I think it was on the order of 0.2V.

Of course, this was in the North Sea. Very salty water.
 
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Electrolysis does not occur if the voltage is less than 1.7 V.. Above that as long as there is some current flowing you will get electrolysis.
 
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