7 hours ago
Pickles glow when you run electricity through them, and researchers finally figured out why
https://www.zmescience.com/science/physi...ow-orange/
EXCERPTS: Stick two metal electrodes into opposite ends of a pickle, hook them up to mains electricity, and stand back. Within seconds, the pickle begins to hiss and steam. Then one end suddenly erupts in a fierce orange glow, as if the vegetable has briefly turned into a lamp.
The “glowing pickle” has been a favorite classroom stunt for decades. The usual explanation is simple: the salty brine conducts electricity, and excited sodium ions produce the orange light. But that’s only part of the story.
After sacrificing more than 100 pickles to science, an electrical engineer at Portland State University believes he is finally closing in on an explanation. And surprisingly, it involves tiny hydrogen explosions.
Joshua Méndez Harper, an assistant professor of electrical engineering, presented the results at the Electrostatics Society of America’s annual meeting in June.
A pickle conducts electricity because its watery interior contains dissolved salt. In water, salt separates into charged particles called ions, which can carry electrical current. A fresh cucumber contains water too, but far fewer dissolved ions, so it conducts much less readily. So far, straightforward enough. But when electricity starts flowing through a pickle, things get considerably messier.
[...] Méndez Harper thinks the two explanations are connected. The electrical current produces hydrogen gas while also heating the brine enough to create vapor pockets. As those pockets form and collapse, electrical sparks can jump between the electrode and the surrounding liquid. Those sparks, he proposes, ignite the hydrogen.
In other words, the pickle may be hosting tiny bursts of combustion, with electrical discharges providing the ignition.
[...] Scientists have looked at this phenomenon for decades. A 1993 Journal of Chemical Education paper showed that the familiar yellow-orange color corresponds to sodium’s characteristic emission. A later 2005 experiment replaced sodium with other dissolved metals and produced differently colored pickles—including pink, purple, and red glows... (MORE - details)
https://www.zmescience.com/science/physi...ow-orange/
EXCERPTS: Stick two metal electrodes into opposite ends of a pickle, hook them up to mains electricity, and stand back. Within seconds, the pickle begins to hiss and steam. Then one end suddenly erupts in a fierce orange glow, as if the vegetable has briefly turned into a lamp.
The “glowing pickle” has been a favorite classroom stunt for decades. The usual explanation is simple: the salty brine conducts electricity, and excited sodium ions produce the orange light. But that’s only part of the story.
After sacrificing more than 100 pickles to science, an electrical engineer at Portland State University believes he is finally closing in on an explanation. And surprisingly, it involves tiny hydrogen explosions.
Joshua Méndez Harper, an assistant professor of electrical engineering, presented the results at the Electrostatics Society of America’s annual meeting in June.
A pickle conducts electricity because its watery interior contains dissolved salt. In water, salt separates into charged particles called ions, which can carry electrical current. A fresh cucumber contains water too, but far fewer dissolved ions, so it conducts much less readily. So far, straightforward enough. But when electricity starts flowing through a pickle, things get considerably messier.
[...] Méndez Harper thinks the two explanations are connected. The electrical current produces hydrogen gas while also heating the brine enough to create vapor pockets. As those pockets form and collapse, electrical sparks can jump between the electrode and the surrounding liquid. Those sparks, he proposes, ignite the hydrogen.
In other words, the pickle may be hosting tiny bursts of combustion, with electrical discharges providing the ignition.
[...] Scientists have looked at this phenomenon for decades. A 1993 Journal of Chemical Education paper showed that the familiar yellow-orange color corresponds to sodium’s characteristic emission. A later 2005 experiment replaced sodium with other dissolved metals and produced differently colored pickles—including pink, purple, and red glows... (MORE - details)
