If water is exposed to high voltage, it will ionize.

In summary: If the current is too high, the coating can be melted away, and the element would become an open circuit.
  • #1
sunchips
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0
if water is exposed to high voltage, it will ionize. What is the minimum voltage needed for that to happen? Thanks!
 
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  • #2
sunchips said:
if water is exposed to high voltage, it will ionize. What is the minimum voltage needed for that to happen? Thanks!
What is the energy required to remove an electron from a hydrogen or oxygen molecule?

AM
 
  • #3
Andrew Mason said:
What is the energy required to remove an electron from a hydrogen or oxygen molecule?

AM
This will only give you an estimate of the ionization potential for H2O(gas). In the liquid state, the number is much lower, due to several effects that are not easy to calculate (you can think of these as described by a local dielectric constant). I believe the number for water is about 1 volt.

EDIT: Yup, the standard reduction potential tables tell me it's 0.83V
 
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  • #4
so, say a circuit is submerged in the water. The circuit requires only a 0.83V to ionize the surrounding waters?!? Wow! I though it wouold be much higher than that!
 
  • #5
Wasn't that for 1 molecule?
So if you had millions of molecules it'd take millions of volts right?
 
  • #6
sunchips said:
so, say a circuit is submerged in the water. The circuit requires only a 0.83V to ionize the surrounding waters?!? Wow! I though it would be much higher than that!
Multiply that by the number of coulombs of charge to get the energy. So the energy to remove an electon from a water molecule in the liquid state is .83eV or .83 x 1.6e-19 C = 1.3e-19 Joules.

AM
 
  • #7
Jarle said:
Wasn't that for 1 molecule?
So if you had millions of molecules it'd take millions of volts right?

so is this true? Thanks!
 
  • #8
No, it's not. It does not take 2 million volts to produce hydrogen from the electrolysis of water (it takes about 2 volts). The Daniell (Cu|CuSO4||ZnSO4|Zn Galvanic) cell produces an EMF of about 1.1V (not millions, billions or an Avogadro number of volts).

The real number will be about 1 or 2V. There will be a deviation from the ideal ionization potential, in a real electrolytic cell, that depends on the electrodes used. An ideal, inert electrode will get you closest to the ideal number. Any other electrode will require an overvoltage to produce the same current as the ideal cell.

sunchips said:
so, say a circuit is submerged in the water. The circuit requires only a 0.83V to ionize the surrounding waters?!? Wow! I though it wouold be much higher than that!
Heard of anyone that killed their cell phone by dropping it in water? Typical phone batteries run at somwhere between 3V and 4V - easily enough to ionize a path through water (if the phone case isn't watertight) and make a short.
 
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  • #9
I'm sorry..I think I didn't explain my situation well enough. I am asking, in terms of say...

suppose we have a heating element submerged in water. (e.g. a coffee maker, or amny other possible everyday things). When the current is passed through the nichrome heating element, will the current ionize the surrounding waters? is it powerful enough?

Sorry if I didnt explain myself well before, and thanks for all your help!
 
  • #10
sunchips said:
I'm sorry..I think I didn't explain my situation well enough. I am asking, in terms of say...

suppose we have a heating element submerged in water. (e.g. a coffee maker, or amny other possible everyday things). When the current is passed through the nichrome heating element, will the current ionize the surrounding waters? is it powerful enough?
To the best of my knowledge, all immersion heaters have an electrically insulating (but thermally conductive) coating over the nichrome element. I'd expect the outer case to be grounded.
 

What does it mean for water to ionize?

Ionization is the process by which neutral molecules or atoms gain or lose electrons, resulting in the formation of charged particles known as ions. In the case of water, ionization occurs when it is exposed to high voltage, causing the water molecules to break apart into positively charged hydrogen ions and negatively charged hydroxide ions.

How does high voltage cause water to ionize?

High voltage has a strong electric field that can overcome the bonding forces holding water molecules together. This results in the molecules breaking apart and forming ions. The higher the voltage, the more energy is available to ionize the water molecules.

What are the implications of water ionization?

Water ionization has several implications, including changes in the pH level of water, the formation of reactive oxygen species, and potential health risks. It can also affect the efficiency of electrical devices that rely on the conductivity of water.

Is ionized water safe to drink?

The safety of ionized water depends on the source of the water and the level of ionization. If the water is from a clean source and the ionization is minimal, it is safe to drink. However, if the water is heavily ionized, it can be harmful to consume due to the potential health risks associated with high levels of ionization.

Can high voltage ionize other liquids besides water?

Yes, high voltage can ionize other liquids besides water. The ability of a liquid to be ionized depends on its chemical composition and the strength of its bonds. Some examples of liquids that can be ionized by high voltage are acids, bases, and various solvents.

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