I’m trying to simply things in dummy terms so I remember it easier rather than memorizing a definition I want to understand it on a basic level. A Neutron is an uncharged elementary particle that equals a protons mass in a nucleus this stabilizing it, I also know that in an atom there has to be equal amounts of neutrons and protons, and that the neutrons act as a sort of binder, so what sort of analogy or explanation could be used to describe it? Does a Neutron sort of act like the Mortar for a Brick Structure? Or like the glue that keeps protons from falling apart?
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Protons are positively charged. Just like magnets, positive repels positive. The “strong nuclear force” attracts protons and allows them to bind in an atom’s nucleus despite them being of the same charge, but the more protons you have, the stronger that repelling force is, eventually overcoming the strong force. The neutrons are also attracted to the protons by the strong force, but are not repelled by electromagnetism since they have no net charge. Having neutrons and protons instead of just protons “allows” atoms to be bigger (higher atomic number) because it increases the strong force interactions in the nucleus without adding charge which would try to push the nucleus apart.
TL:DR protons push each other apart because they have the same charge, neutrons help pull protons together with more force than is pushing them apart
There are two fundamental forces that matter on the scale of an atomic nucleus: the electromagnetic force, and the aptly named strong nuclear force.
The electromagnetic force is long range in the same way that gravity is, and it causes the protons to repel each other. For all intents and purposes, it doesn’t care about the neutrons.
The strong force is several times stronger than the repulsion between the protons. It acts on both protons and neutrons to bind them together, and is very short range, like about as far as the proton or neutron next to it.
If you had all protons, their charges would keep them apart, or if there were only two then one of them would turn into a neutron.
As soon as you have neutrons, they can help hold on to the particles next to them, and they also create a little space between the protons. Exactly how many neutrons you need depends on how many protons you have. For light nuclei, it’s about 1:1. For heavy nuclei, you need more neutrons. For really heavy nuclei, they just won’t stay together at all, because all the protons see each other and the neutrons can only deal with what’s right next to them.
You can think of the neutrons as child minders and the protons as kids who want to fight each other. They can only reach the kid right next to them to calm him down, and also it’s a little harder for the kids to get at each other.
Eventually, when there are too many kids, no amount of supervision can keep them in line.
Atoms are constantly under two forces, the strong nuclear force and electromagnetic force
The strong nuclear force holds atoms together but has weak range and is a strong force
The electromagnetic is a weaker force but with higher range
Neutrons are used as packing material between protons, so the protons don’t repeal each other as much
For elements 1-20 (calcium), the most stable configuration is 1 neutron for every proton, however after calcium you start having issues which changes the most stable configuration to more neutrons than protons
If there’s not enough or too much packing material the electromagnetic force is strong to rip the atom apart, this is also what limits the size of atoms since the strong nuclear force has much smaller ranger than the electromagnetic force does
>I also know that in an atom there has to be equal amounts of neutrons and protons, a
That is not true. You do have a 1:1 ratio for stable isotopes with 20 protons or below, but after that you need more neutrons the protons. Element 20 is Calcium and Ca-40 with 20 neutrons is sable. but when you reach Element 21 is Scandium it is Sc-45 that is stable and it has 25 neutrons this is a ratio of 1:1.25
Lead has 82 protons and that is the most of any stable element. The lightest stable isotope Pb-204. That means it has 204-82= 122 neutrons and a ratio of 1:1.51
If you look at elements with more protons you will find the one that has the longest half-life has proton to neutron ratio that grows. U-238 is the last found in larger amount in nature it has 92 protons and therefore 146 neutrons for a ratio of 1:1.59
It is possible to have fewer neutrons than protons and be a stable element, there is only two of them. Hydrogen-1 is the obvious answer, it only has a single proton and no neutron. Helium-3 is the other and is stable with 2 protons and 1 neutron.
Look at https://en.wikipedia.org/wiki/Neutron%E2%80%93proton_ratio#/media/File:Isotopes_and_half-life.svg for a graph will element and the proton to neutron ratio. IT is the black squares that are stable and you see they diverge from the Z=N line which is a 1:1 ratio
Think of it as glue. Neutrons hold the nucleus together using the strong nuclear force which overcomes the repulsive electromagnetic force between the protons.
There doesn’t need to be the same number of neutrons as protons in a nucleus. In some cases they two are equal (e.g the most common isotopes of helium and carbon have 2 and 6 protons respectively as well as 2 and 6 neutrons each).
But for lighter elements you can have fewer neutrons (such as the rarer isotope helium 3 with two protons but only one neutron), but it is more common to have more neutrons than protons (e.g carbon 14 which has six protons and eight neutrons).
As you move to heavier elements, an ever greater proportion of neutrons are required to overcome the repulsive forces of the protons. By the time you get to uranium you need 146 neutrons to hold the nucleus together from the force of 92 protons – and even then, the nucleus is barely stable.
The nucleus of an atom is held together by the strong nuclear force. Neutrons and protons aren’t actually elemental particles. They’re each composed of three quarks. The force that keeps these quarks together also keeps the nucleus of atoms together. The positive charges of the protons repel each other but the strong nuclear force of the protons and neutrons attract each other. An atom’s nucleus needs enough neutrons so that the attraction of the strong force is greater than the force of the protons repelling each other.
A couple of things from your question I want to point out. Neutrons are not elementary particles because they are made of even smaller particles called quarks. If that’s not relevant to what you need to know RIGHT NOW, then don’t think too hard about it. That’s just a terminology mix-up.
Also, there is no requirement for atoms that says they must have equal numbers of protons and neutrons. Hydrogen’s nucleus is a single proton. Carbon can exist in several different “isotopes” or atomic weights. What changes is the number of neutrons. Carbon-12 is the most common with 6 protons and 6 neutrons. Carbon-14 also exists with 6 protons and 8 neutrons. The thing I think you perhaps misunderstood is that some combinations of protons and neutrons cause unstable atomic nuclei. These atoms are radioactive and will decay, but they can still exist for a long time. Example: Carbon-12 is stable, and Carbon-14 is radioactive. That’s part of the basis of how Carbon dating works.
This is way beyond the scope of what you asked, but I want to make sure that you have accurate info.
Honestly, for an ELI5 answer, yours isn’t bad. The only thing I’d add is that the number of neutrons doesn’t exactly have to match the number of protons. Atoms are just more stable that way, generally.
Usually, an atom will have the same number of protons, neutrons, and electrons, but not always.
# of protons tells you what element it is.
A different number of neutrons results in an isotope.
A different number of electrons results in an ion.
Because electrons are so incredibly tiny, changing the amount of them really only affects the charge of an atom, which changes how it bonds and interacts with other atoms. However, because nearly all of the mass of an atom is in its protons and neutrons, changing the amount of neutrons will actually change the properties of the atom
I will add a simple ELI5 explanation, since pretty much every other point has been addressed.
There are two major forces at play in the atomic nucleus: electric and nuclear. Treat each particle in the nucleus like a person. The protons (+) repel each other from a distance. I think of this as protons blowing against each other, and the closer they are together the stronger the repulsion. However, if protons get close enough they are able to link arms together (this is the attractive nuclear force). With just a bunch of protons and no neutrons, the protons will be able to blow each other away and never link arms, but the neutrons do not blow anything away because they are electrically neutral, so they assist in holding everyone together. The thing about the nuclear force (linking arms) is that you can only do that when you are very close to your neighbors, which is why in general heavier elements are less stable.
By the way, neutrons are not elementary particles, but that’s not important here.
I can’t offer a full explanation but I will say that the amount of protons and neutrons does not have to be the same. For an atom to be neutral (ie not an ion) it has to have equal amounts of electrons and protons, but since neutrons don’t have any charge they won’t affect the atom in the same way.
The same atom with different amounts of neutrons is called an isotope, some examples of these are carbon-14 and uranium-235. The numbers after the name in this case tells you the amount of neutrons that are in the atoms nucleus.
More neutrons = more mass and it can make the atom more or less stable. (Atoms with obscene amounts of neutrons will fall apart, which is what causes radiation). Different amounts of neutrons however will not change the fundamental characteristics of the atom in question. So no matter how many neutrons you slap on to an atom it will remain the same element with the same properties
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