electric water

[Cogman]

Ok, this was kindof a strange thing that happened to me. I was walking in from track, and of course I was exasted, my mouth was dry, and my feat where kindof dragging. Our school has a carpet floor btw. I went to get a drink of water, ours has a little handle you push down to get water, all plastic. I bent over to get a drink and ZAP. right through my tonge I felt an electric current from the water (No joke).

Well to make sure I wasnt crazy, I made myself look crazy and shuffled around in a circle to get a charge. Then I tried again.. Again a shock from the water.


So heres the thing. Water without some solute in it should not conduct electricity right? This water should be fairly clean, and it definitly was not salt water. So what would be present in it that would cause a zap.

(We dont use floride in our drinking systems, small town. Every once in a while they do dump a little chlorine in the water though)

 

[buleyb]

i'm not expert, but I was under the impression that water will conduct, albeit poorly, even if it is rather pure.

It only needs to conduct to the first trace of metal pipe...

 

[Peter]

Electrostatic charges pile up to quite surprisingly high voltage. That'll easily discharge even through a poor conductor like water.

 

[AluminumStudios]

Static can build up to levels where it it feels like a bit more than a zap, plus static (and high voltage in general) likes to travel along the surface of things, not through them, so it can travel along the surface of the stream of water just fine even if the clean water is a somewhat poor conductor.

 

[PowerEngineer]

While it is true that 100% pure water does not conduct electricity, you're unlikely to ever find that coming out of a water fountain. Even a very small amount of impurities make water a fine conductor (remember all those classic warnings about not standing in a puddle while changing a light bulb or dropping your hair dryer in the bath tub).

 

[cjdomer04]

Poor conductor still is a conductor, unless it is 100% DI water. What I like is that you got shocked and did it again.

 

[Mark R]

The most important concept about static charge is that the potentials can be huge - potentially 50,000 - 100,000 volts. This can discharge through short distances of air, through water or another route.

Water is a poor conductor of electricity, with ulta-pure water being particularly poor (but nevertheless a conductor), but the very high voltages could generate a significant current through even a very high resistance. Indeed, the tongue is a sensitive part of the body, and a current of 0.5 - 1 mA can often be detected as a slight tingle.

Given the right conditions, I'm sure it would be possible to replicate this experiment with 100% pure water, and still get a slight shock. (Quick top-of-head calculation suggests a resistance of about 10-50 MOhm for a waterfountain type squirt of pure water).

 

[JSSheridan]

Interesting that you don't have fluorides in your water system. Still, I imagine that you are drinking hard water from your system as opposed to soft water. Calcium and magnesium ions are present in hard water, which also provide a path for current to flow. Also, hard drinking water can contribute a small amount toward total calcium and magnesium that a healthy body needs. Peace.

 

[rgwalt]

No matter how clean you THINK your drinking water is, it still has small levels of minerals (ions) which aid in conduction.

R

 

[jagec]

Originally posted by: PowerEngineer
While it is true that 100% pure water does not conduct electricity,

not *exactly*...water does disassociate to H+ and OH- at a very low (10^-14) concentration, even 100% pure water, so it would conduct electricity. Very poorly though.

 

[Jamie571]

jagec is correct. I work with YAG lasers that use chilled water to cool the YAG chamber. To fire the induction lamps takes about 10,000 Volts, so the cooling water must have an extremely low conductivity (which is measured in micromhos). We start with what is labled as 100% pure filtered drinking water which like jagec said does conduct electricity it is about 600 micromhos. To lower the conductivity, we use a deionizer filter that on contains some type of deionizer compound. This lowers its conductivity to 2 to 4 micromhos.

 

[JediJeb]

Absolutely pure water still has conductance, the resistance it measured at 18.2Mohms. The resistance is what is used my most ultra pure water systems to show the level of purification. Drinking water normally only has a resistance of 1 Mohm or less, so it is fairly conductive.

 

[Cogman]

Thanks for the posts.

... What I like is that you got shocked and did it again.

What can I say, Im a geek . I still shock myself on the trampline just because I like being shocked, dont know why, just always liked it.

 

[Lico]

Originally posted by: jagec

Originally posted by: PowerEngineer
While it is true that 100% pure water does not conduct electricity,

not *exactly*...water does disassociate to H+ and OH- at a very low (10^-14) concentration, even 100% pure water, so it would conduct electricity. Very poorly though.

isn't the concentration of H+ and OH- each 10^-7? ie. pH 7 and pOH 7?

 

[jagec]

well, I should have said the disassociation constant is 10^-14. So yeah, the concentration of each species is 10^-7. If I remember it right.