Is the Leyden Jar still charged even after discharging the metal parts?

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The Leyden jar retains charge even after discharging its metal parts because the charge resides within the glass, not just on its surface. Discharging the metal components does not ionize the copper; it simply removes excess free electrons. When the jar is reassembled, any remaining induced charge in the glass can still create a spark when the metal parts are touched together. This phenomenon occurs because the electrons flow from the copper through the body to the ground. The charge in the glass remains even after attempts to discharge it, indicating that the Leyden jar can still hold energy.
cragar
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A couple of questions about the leyden jar . When i first charge up the leyden charge with a potential difference and then i dissemble the jar and i touch the metal parts of the jar to discharge them , Am i ionizing the copper that the jar is made of ,
And question #2 let's say I discharge both the metal parts of the jar and then I re-assemble the jar , and then i touch the inside metal part to the outside and i still get a spark .
Is the reason for this , because we did not discharge the glass so there is an induced charge on the glass , and then when we reassemble it , it cause charge separation on the copper parts of the jar .
 
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Ionisation is the removal or addition of an electron from/to a neutral atom.
Your copper is not neutral, it has extra charges attached to it. So in removing those charges you are not 'ionising' the copper - simply 'discharging' it.

And yes, the charge is in the glass, not just on it, but inside it. even if you try to discharge it by wiping, it will remain charged deep inside.
 
but when we discharge it , we are physically removing free electrons from the material
and when we touch it the electrons flow from the copper through our body to the ground .
Thanks for your response by the way.
 
Free electrons, not bound ones. You are not turning the copper atoms into ions.
 
ok , but the electrons came from the material , and are now transferred to the Earth .
 
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