Why is it than when an atom loses or gains an electron (or a neutron, or a proton) it doesn’t turn into another element?

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I’m sorry if this is worded wrong, my science vocabulary isn’t all that in English.

So atoms can lose or gain electrons, protons and neutrons, but when they do, they turn into a different version of that element (ie. an iron cation) instead of another element that has that same amount of neutrons, protons and electrons. How do these changes make an element different, but not enough for it to turn into a different thing?

In: Physics

Protons are like the ID of an element, if it somehow changes the amount of protons (eg. radioactive decay) it becomes a new element.
If it changes the neutron amount it becomes a different isotope. Isotopes are the same element but with different nuclear mass (i.e. neutrons change amount)
If it changes electron amount it becomes an ion, it changes its electric charge (eg. Fe+, it lost an electron and became electrically charged positive, since it now has more protons, particles with positive charge, than electrons which have negative charge)

If an atom loses or gains a proton they *do* change in to a different element. The number of protons, if we simplify a bit, is what defines an element. Hydrogen always has one proton. If it gains a proton it is no longer hydrogen, it is now helium.

Losing or gaining neutrons is what turns elements in to different isotopes of that same element. The proton count is the same, but because neutrons affect the stability of the nucleus / atom core the isotope may not be as stable or behave somewhat differently, despite being the same atom.

Electrons for the purpose of this discussion don’t really matter, as they aren’t part of the nucleus. They just hover around and aid the atom in reacting to other stuff.

We define an element by the number of protons. If you change the protons, it becomes a different element.

If you change the number of neutrons, it becomes an isotope of that element. This is because the neutrons don’t participate in electromagnetic forces which is one of the fundamental forces behind chemical reactions (note that the additional mass of neutrons *can* impact chemical reaction rates, especially when the base element is light, like hydrogen.)

When you change the number of electrons, it becomes an ion of that element.

It does turn into another element when it gains a proton. Element names are based on the number of protons in a substance. So, in the sun when Hydrogen collides with another hydrogen, it can Fusion to become Helium.

Changing the number of neutrons changes it from one isotope of an element to another one. So Carbon-14 has 8 Neutrons and Carbon-12 has 6 Neutrons.

Changing the number of electrons turns it into different Ions of the same material.

The reason Protons are so important, is protons set the amount of electrons are usually in the atom and molecule, and changes the likelihood of getting another electron or losing an electron. Atoms are trying for 2 things, electrical neutrality (same number of electrons as protons) and a stable, low energy configuration of electrons, and those two competing ideas change the properties of the various elements.

The reason why they look at proton number rather than electron numbers is electrons are a less permanent configuration, as it proton numbers are much, much more stable than electron numbers.

It does change if it loses a proton

For example plutonium 244 decays into uranium 240 through alpha decay

https://en.m.wikipedia.org/wiki/Alpha_decay