The core, the nucleus, of an atom consists of positively charged protons and of neutrons that do not have any charge. The nucleus in its entirety is considered to be positively charged. Surrounding the atomic nucleus is a cloud of electrons. Electrons are negatively charged. If the number of electrons are the same as the number of protons, then the atom is electrically neutral. There is electric equilibrium.

Source: https://www.sciencefacts.net/atom-2.html (2026-08-31)

This equilibrium can change. This happens when the number of electrons is unequal to the number of protons. The atom is then called an ion. If there are more electrons than protons, the ion is negatively charged. If there are less electrons than protons, the ion is positively charged.

Source: https://sciencenotes.org/what-is-the-difference-between-an-atom-and-an-ion/ (2026-08-31)

Any object or material that contains ions is no longer electrically neutral. It has an electric charge or "potential". Between to differently charged objects or materia, there is potential difference or "voltage". This electric imbalance always wants to equalize: atoms "want to be" neutral. Ions are either going to give away or receive the amount of electrons needed to achieve this equilibrium. This happens when two differently charged objects or materia directly touch or it can happen by influence in an electric field. Until a charge is equalized it remains and is considered static.

An example of charges equalizing by direct contact is when two differently charged people touch each other and experience a shock. Or when you happen to have collected an abundance of electrons, thus creating negative ions, and then you touch a differently charged object. Ouch (sometimes).

Source: https://thors.com/manufacturing-courses/manufactured-products/electrical-and-electronics/electrostatic-discharge-esd-basics/ (2026-08-31)

An example of charges equalizing through electric fields is lightning striking the ground. The potential difference between clouds and the ground grows so big that matter between them is ionized and finally, when the potentinal difference is big enough, the charges equalize in the form of visible current - lightning ⚡.

Source: https://www.savemyexams.com/igcse/physics/oxford-aqa/16/revision-notes/electricity-and-magnetism/electrical-circuits/static-electricity/ (2026-08-31)

Another example is dust particles pulled towards oppositely charged electric devices in your home. Or styrofoam on a cat.

Source: https://commons.wikimedia.org/w/index.php?curid=60287175 (2026-08-31)

To be continued. Meanwhile, some questions that popped up:

1. What determines the amount of voltage needed for a current to discharge in a scenario where the opposite charges never touch but only ever interact through the electric field? Some assumptions of mine: distance to each other, (air) humidity, medium (air, vacuum, other), resistance, interference from other electromagnetic waves...?
2. What creates ions, except for the above mentioned physical friction? What natural phenomenon or scenarios kick electrons off or shoves them onto atoms? Is this what we artificially do in batteries? Creating negative and positive ions to create voltage?

(just testing)

Test comment. I can't create a post 'mods only'.

Yup, seems to work as intended.

Great! Then all is good! 😁

Thanks a lot! 😃❤️

just making sure those last 2 weren't flukes

Much appreciated! 😁🩵

Upvoting for styrofoam cat, that's quality stuff.

Teacher: Say after me, class! "Static."
Class: "Styrofoam."
Teacher: "Electricity."
Class: "Cat."

To answer one of your questions, electrons are often the most stable when they fill a complete shell around the nucleus. So an atom with 7 electrons and one missing electron could easily hold an 8th electron, get a negative electric charge, and chill like that. Imagine you had 11 eggs in a carton that fits twelve. If you got an extra egg, your carton would be full, and strong.

One example is the Chlorine atom. It has 7 electrons in its outer shell, and would be more stable with 8.

Atoms that have a complete electron shell, and then extra electrons on top of that, are sometimes more stable when they can give away their extra electrons and exist as a positive ion. Imagine if you had 13 eggs, in two one-dozen egg cartons. You would be more stable with trading that one extra egg away.

One example is the Sodium atom. It has one electron in its outer electron shell, and would be more stable giving it away.

The consequence of this is if a neutral sodium atom and a neutral chlorine atom ever were to bump into each other, the laws of stability say that they'd be most likely to trade an electron. Sodium would give away its outer electron, and chlorine would accept it. Sodium would get a +1 charge, and chlorine would get a -1 charge.

Since this is extremely likely, that is why elemental sodium and chlorine are rare, reactive, and short lived in nature, but their ionic forms, Na+, Cl- are super stable and common: the oceans are full of the stuff, and when water dries out, they pull together from their electric charge and form NaCl, aka table salt.

This is also why chlorine gas is so dangerous: it is really good at taking electrons away from other things, including animal tissues.

And this is why elemental sodium reacts with air and water so easily -- it is good at losing its electron to other things.

Question #1 is more complicated for me. One equation you will see later in the textbook is Ohm's Law, which says that the voltage is equal to the current times the resistance, V = IR.

You're right that the humidity of the air, the distance, and the medium affects the resistance. I'm not advanced enough to know about interference, but you're probably right about that too.

If we look at the case of static electricity, we could ask, "what is the voltage needed to cause a spark?". To answer that question, you'd need to know the resistance of the air (which also varies based on the distance the spark has to travel) and the current of electricity passing through the spark. The higher the current, the higher the voltage needed, given the same resistance.

Static electricity tends to be low current, and high voltage, to overcome the electrical resistance of the air, over very small distances.

Lightning is doing the same thing, but with much greater resistance to overcome (large distances through the air), higher current available in the clouds, and much higher voltages necessary to overcome the resistance times current.

But in both cases, those three variables will follow the relationship V = I * R, aka Voltage equals Current times Resistance.

uhhhhh but you don't deal with atoms usually you deal with something bigger. if you have a chunk of metal, then all the free electrons form electron gas, which can move freely around, and some can be taken out and some can be added and nothing bad happens too fast

as for 1. i think it's easier to go backwards. when you move some charge between two things, these two things will develop voltage between them. how big potential difference is depends on how widely can these two things disperse that extra charge. measure of that property is called capacitance, and it's nicely related to these other values: Q = U * C. energy stored is: E = U^2^C/2. capacitance depends on geometry of dielectric between these things, and dielectric constant. if there's some resistive component then over time that charge will be lost. there does not need to be movement of charge between these two things, it can happen between these and other things and it all works the same. charge is conserved, so if you allow two charged things to attract each other then voltage between them drops because capacitance increases, and in the other direction if you do work on charged capacitor and move plates away then voltage increases

1. there's plenty salts that are composed of pairs of ions, sort of. batteries transform something into something else while moving electrons around. this also requires ions to move within battery but sometimes not much changes. for example in lithium battery, all that is happening is that lithium moves from graphite to cobalt oxide

arcing has extremely nonlinear resistance, it doesn't work like this at all. it happens when there is some voltage per mm reached, then voltage across the arc is tiny when current is flowing

and what happens when you have more atoms. well it's a bit more complicated. atoms have some energy levels, and some of them are occupied and some above them are not. it turns out that when you put two atoms together, some of these energy levels combine in a specific way, and you end up with two new ones. but we only need to look at those near the edge of where electrons are. when you combine many of them, you can end up with a continuous band of energy levels where electrons can sit.

if that band is partially filled, electrons can go wherever, because external electric field makes it so that electrons in some places have slightly lower energy than in others. that means there is flow of electrons until new equilibrium is reached. that means there's no barrier to electron movement, this thing is called metal

if electrons sit in one band and all of them fit there, and there's another band way up that is empty, electrons can't move freely until something provides enough energy to jump to the other one. this is called insulator

if the gap is small enough, then there's small number of electrons that will jump from one to the other because of thermal movement, and this is called semiconductor and it's way more complicated than that

Thanks for the elaborate answer! This will take some time for me to digest, since I'm a complete novice in this field. Litterally just opened the books. Thanks again! 😊

Thanks for the headsup on Ohm's Law! Looking forward to exploring it! I think it could be as soon as the next section in this chapter. 😁

Just a kind reminder to be as kind and educational as possible when giving answers! 😊

Wow! That was amazingly well explained!

Atoms that have a complete electron shell, and then extra electrons on top of that, are sometimes more stable when they can give away their extra electrons and exist as a positive ion. Imagine if you had 13 eggs, in two one-dozen egg cartons. You would be more stable with trading that one extra egg away.
How interesting that some atoms "like" their ion state! This textbook says that atoms always want to discharge or cancel out any potential, but I guess that's just the book's way of introducing the subject?

This is also why chlorine gas is so dangerous: it is really good at taking electrons away from other things, including animal tissues.
My four week vacation just began - and finishing the textbook is one of my goals - but this is the first bit of newly found knowledge that I'm going to brag about at work! Haha!

Thanks again!

oh and also. if you are forceful enough you can just inject electrons into whatever. this is how these frozen lightning plastic sculptures are made, electrons are put within plastic block, as high energy electron beam, it makes more sense to think of it as radiation, and they carry just enough energy to decelerate and stop within plastic. then all that uniform space charge gets discharged when grounded nail (zero volts) is struck on one side, which makes arc, and arc is plasma which is conductive, which makes more dielectric breakdown to happen because now that plasma is grounded, and so it propagates across the entire block. this is what i mean https://www.youtube.com/watch?v=8a3GfozsU0s that blue light is electron beam striking plexiglass. nail is needed because edges lose charge faster and the center part is insulated

Holy crap, what did I just watch 😱 Thanks for sharing and explaining!

we have such sights to show you

it might make more sense as a diagram https://en.wikipedia.org/wiki/Electronic_band_structure#/media/File:Band_filling_diagram.svg

This shit right here is why I love Lemmy. Hope you carry on you magnificent bastard.

Haha, this completely caught me off guard! 🤣 Thanks!!! ❤️

I'm doing this because translating anything at all requires at least some intellectual understand of the subject, which helps me learn faster! I explained this in much greater detail in the original description of the community, but PieFed threw me an error and it all got deleted.😩