The sparking phenomenon of KCl is partially explained by the "plasma grape" phenomenon, especially since grapes contain potassium and sodium.
Here is a video of the grape effect - which goes part of the way to explain the more general case, https://www.youtube.com/watch?v=wCrtk-pyP0I At about 6:40 in the video Veritasium shows the emission spectrum of the plasma which is basically a spike of potassium with contribution of sodium. A further contribution from hydrinos is doubtful due to the absence of Lyman line broadening. The self-focusing standing wave and internal reflection of the microwaves in grapes provide heat but no plasma since the GHz photons are non-ionizing, and essentially most of the plasma consists of potassium and sodium ions indicating that they are somehow activated. Since grapes contain sugar which ignites with the sparking - a situation of using no "fuel" (plain KCl solution) would be more impressive. A further refinement would be to fill a pair of tiny balloons (about the size of grapes) with a KCl solution then nuke them and compare that sparking to the grapes -- in order to gauge the contribution of "fuel" (sugars). ---------- Potassium atoms are strongly sensitive to a magnetic field. This could relate to what is happening in the experiment where microwave radiation is applied to KCl (at least in the sense of ultra strong coupling to the gigahertz waves from the oven.) The most sensitive magnetometer available , named SERF - comes from Princeton and consists of a cell containing potassium vapor and a buffer gas. The unpaired electrons on the potassium atoms are spin-polarized so that a probe detects the precession of spin in the presence of a magnetic field. This device is capable of incredible sensitivities on the order of 10-18 Tesla, 1000 times more sensitive than a SQUID detector. Thus microwave radiation, already efficient, can be utilized in a more efficient way - perhaps becoming strongly ionizing and splitting water. IOW it is possible that the extreme spin sensitivity of potassium to RF is a little understood effect -- maybe one looking for an application. ----------------------------- I like the sound of "something strange going on." Heck, it might be worthwhile to try various mixtures of KCl and NaCl to see if there is an obvious particular ratio where the sparking is maximized. Mills uses a pinhole technique for finding UV where he actually drills a sub-mm hole into the reactor wall with line of sight to the plasma, and mounts and glues a photocell UV detector chip over the hole - but that is for a vacuum reactor. Robin may have experience with this...? Michael Foster wrote: Some of the sparking looks a little too far from the surface of the glass container to be contaminated by it and there's a lot of sodium spectrum being displayed. So something strange is going on, I think.
