What is the source of the Kelvin Water Dropper effect?

[bmarc92]

From a classical mechanics perspective I understand the force interactions leading to the phenomenon, but from a matter perspective, what is a "positive" or "negative ly" charged water stream?

Is this referring to the spontaneousH(+) + OH(- )formations?

 

[TeethWhitener]

The charges come from autoionization of water, yes, as well as any dissolved ions that happen to be in the water. Ultimately, the energy source that drives the charge separation is gravitational potential energy.

 

[Borek]

Also google solvated electron.

Apart from ions flowing water is full of separated charges, this is in principle not much different from the separation of charges that occur when combing hair (or any place where there is some friction). The difference is water is a reasonably good conductor (unless ultra pure), so there is no charge build up. Kelvin dropper just amplifies these effects.