MIT Physics Demo -- Conductivity of Ionized Water

A light bulb is placed in series with two copper plates immersed in de-ionized water. Touching the plates closes the circuit, lighting the bulb.

When kosher salt is dropped into the de-ionized water, the salt dissolves, causing ions to be dispersed throughout the liquid. The free ions allow current to flow through the water, which completes the circuit and lights the bulb.

Most water we encounter in everyday life is not de-ionized and contains impurities with dissolved ions. This is why we know water as a good conductor, and why we shouldn't use electronic devices around a bathtub, for example.
See original video on MIT TechTV - http://techtv.mit.edu/videos/798

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Education

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[scart1992]

If your going to comment on a video and diss on it maybe you should learn how to spell or use correct english. "plane" as in the thing you ride in. It should be "plain" water. Just like "break" and "brake" Get it? Good =]

[HoneycombAgent]

Don't try this at home!!  You could electrocute yourself.

[KakHazhar]

Beautiful.

[lovelplants]

so salt must be kosher huh... great demo.. just don't do experiment like that if your hand is wet.. lol...

[rabbimarcus]

Must the salt be kosher? What if the salt is treif?

[p4ndiamond]

I would use that to beat my meat

[JapanIsShinto]

@everynameseemstobe Because he bumped the table while flipping the switch.

[everynameseemstobe]

can anyone explain why the water starts vibrating when he flips the switch?

[gennaman2bit]

@aquapulsefuel atmosphere is not conductive, but the potential difference between the sky and the earth (sometimes between 2 clouds) can be enaught to ionize the air, so the lightning discharge the potential and the air become non conductive again. In ionosphere there are charged particles coming from the sun radiation and cosmic rays.

[SpiritualWidow]

That would be an excellent test for deducing which healthy additive to use for conducting electricity through water for ionization. Do you know any of these in the least amounts, which would do best. You used a lot of kosher salt, but how about less and unrefined/unprocessed salt or sea salt?(minerals) or epsom salt in this experiment, and how about iodine (liquid kelp), desolved okinawa calcium (loads of minerals) spirulina or baking soda in what dosages?...lol Guess that might be my prob

[aquapulsefuel]

So why does the atmosphere conduct with lighting. Is there ion up there. Is this a ionosphere ?