ed
megohms/cm.
ost
has
have > active sites.
Water films are essentially liquid water. The first layer of water molecule s may bond more firmly to the adsorbing surface than they do to other water molecules. but the layers above that are just water.
The water in the surface film will self-ionise to much the same extent as d oes in the bulk liquid, but that conduction is confined within the film (un less the adsorbing surface is conducting, but in that case the water film w on't make much difference to the situation).
ts)
The ultrasonic nebuliser used to make the air humid in the first presumably provides most of the charge carriers seen - the small droplets carry a cha rge from the instant of their creation, and they will last longer at higher humidities.
It's not the humid air that doing the conduction, but the fog particles sus pended in it.
One of the cuter effects of applying a high electric field to an even sligh tly conductive surface is to deform it into an array of spikes, which can b e sharp enough to drive field emission at the tips of the spikes.
This is what sustains arc discharges (though tungsten electrodes don't erod e as fast as water electrodes would).