Chemistry 101
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You see,Originally posted by shadowlunar:Found this on the Net.
In physics, the proton (Greek proton = first) is a subatomic particle with an electric charge of one positive fundamental unit (1.602 × 10−19 coulomb) and a mass of 938.3 MeV/c2 (1.6726 × 10−27 kg), or about 1836 times the mass of an electron. The proton is observed to be stable, with a lower limit on its half-life of about 1035 years, although some theories predict that the proton may decay. The proton and neutron are both nucleons.
The nucleus of the most common isotope of the hydrogen atom is a single proton. The nuclei of other atoms are composed of protons and neutrons held together by the strong nuclear force. The number of protons in the nucleus determines the chemical properties of the atom and which chemical element it is.
Protons are classified as baryons and are composed of two up quarks and one down quark, which are also held together by the strong nuclear force, mediated by gluons. The proton's antimatter equivalent is the antiproton, which has the same magnitude charge as the proton but the opposite sign.
In chemistry and biochemistry, the term proton may refer to the hydrogen ion, H+. In this context, a proton donor is an acid and a proton acceptor a base.
For more info, click here
proton = +ve charge
neutrons = -ve charge
Opposite charge attracts and inside a nucleus, there must be equal number of protons and neutrons for the nucleus to be stable. I remember that there are many cases when neutrons < protons. So there will be instability in the nucleus. So the nuclear binding energy comes in because of this differeces. So the question I'm interested is why this energy can appear when there is a differences in number b/w protons and neutrons? Contradict the like charge repulse and unlike charge attracts theory leh.
Hope someone can answer. -
gluons.
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Neutrons have no -ve charge. Electrons haveOriginally posted by The return:You see,
proton = +ve charge
neutrons = -ve charge
Opposite charge attracts and inside a nucleus, there must be equal number of protons and neutrons for the nucleus to be stable. I remember that there are many cases when neutrons < protons. So there will be instability in the nucleus. So the nuclear binding energy comes in because of this differeces. So the question I'm interested is why this energy can appear when there is a differences in number b/w protons and neutrons? Contradict the like charge repulse and unlike charge attracts theory leh.
Hope someone can answer.
Neutrons = protons + electrons
And no, there is not necessary equal no of protons and neutrons. In fact, neutrons > protons (look @ periodic table!) Why? Cos the neutrons are the ones which will interact with each other to give the electrostatic forces of repulsion while neutron-protons will interact to give strong nuclear force. -
They don't know lar. They will always tell you it is facts and please accept it. Haiz.......Originally posted by deathscythe99:There's the claim of the presence of the particle graviton, which they are trying to assess whether it actually is present.
Anyway, you can GOOGLE IT LAR!
Read this: http://en.wikipedia.org/wiki/Gravitational_force
U shld ask a prof lor -
What is this words?Originally posted by sgFish:gluons. -
Or u asked the wrong one?Originally posted by The return:They don't know lar. They will always tell you it is facts and please accept it. Haiz.......
This is actually in the realm of physics
How old are u...? -
Ops, my bad. I forget my chemistry. Then will can protons be hold together for goodness sake. Like charges repulse.Originally posted by deathscythe99:Neutrons have no -ve charge. Electrons have
Neutrons = protons + electrons
And no, there is not necessary equal no of protons and neutrons. In fact, neutrons > protons (look @ periodic table!) Why? Cos the neutrons are the ones which will interact with each other to give the electrostatic forces of repulsion while neutron-protons will interact to give strong nuclear force. -
Repulsion is due to electrostatic forces, these are short ranged.Originally posted by The return:Ops, my bad. I forget my chemistry. Then will can protons be hold together for goodness sake. Like charges repulse.
Attraction, is due to the presence of strong nuclear attractive force -
No lar,I always ask the pro who teach that subject and if I ask too much, they will ask me to go and accept it and they like not too sure like that.Originally posted by deathscythe99:Or u asked the wrong one?
This is actually in the realm of physics
How old are u...? -
Really?Originally posted by The return:No lar,I always ask the pro who teach that subject and if I ask too much, they will ask me to go and accept it.
Who's the prof...care to sharE?
Then I can ask him same question whahahaha.
BTW...how old are u...seriously? -
Originally posted by deathscythe99:
I mean how can a protons with +ve charges and neutrons with no charge be hold together in a necleus so msyteriously with that mysterious energy helping the necleus to be stable. I find it hard to imagine.
Repulsion is due to [b]electrostatic forces, these are short ranged.
Attraction, is due to the presence of strong nuclear attractive force[/b] -
I already said....there exist these 2 forces.Originally posted by The return:I mean how can a protons with +ve charges and neutrons with no charge be hold together in a necleus so msyteriously with that mysterious energy helping the necleus to be stable. I find it hard to imagine.
U must accept that there is such a thing as FORCE...
Moreover, there's the angular momentum to ensure that it is all kept together...so, why not? -
Hmm... Don't know you much. Can don't tell you or not.Originally posted by deathscythe99:Really?
Who's the prof...care to sharE?
Then I can ask him same question whahahaha.
BTW...how old are u...seriously?
I think you can guess my age liao lar...
Seriously, the most pro I know only teach what he/she knows. Beyond that, he's having trouble explaining. -
Originally posted by deathscythe99:
I am talking about protons inside a nucleus lar.
I already said....there exist these 2 forces.
U must accept that there is such a thing as [b]FORCE...
Moreover, there's the angular momentum to ensure that it is all kept together...so, why not?[/b] -
Originally posted by deathscythe99:
But when the number of protons inside the nucleus increases, shouldn't the repulsion also increases and makes the nucleus extremely unstable? Something must have been holding the nucleus together. If a force or energy exist out of no where to hold them together, then there is where I got lost.
Repulsion is due to [b]electrostatic forces, these are short ranged.
Attraction, is due to the presence of strong nuclear attractive force[/b] -
Wah, how come so quiet liao. Hope someone can help answer my doubts.
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Originally posted by deathscythe99:
Hiya,
I already said....there exist these 2 forces.
U must accept that there is such a thing as [b]FORCE...
Moreover, there's the angular momentum to ensure that it is all kept together...so, why not?[/b]
I thought angular momentum only applies in mechanics? How come can applies in the behaviour of protons. I am not too good in chemistry and need to solve this doubts. -
Forces in opposite directions cancel out one another. If an inward force is balanced by an outward force, that object is not going anywhere.Originally posted by The return:But when the number of protons inside the nucleus increases, shouldn't the repulsion also increases and makes the nucleus extremely unstable? Something must have been holding the nucleus together. If a force or energy exist out of no where to hold them together, then there is where I got lost.
As deathscythe has explained time and time again that the electromagnetic repulsion of the protons is countered by the attractive nuclear force caused by the interactions between quarks and gluons. (within the elementary particles)
With increasing number of protons and neutrons, the electromagnetic repulsion by the increased protons increased as well. But this is again countered by the increase in nuclear force too as the number of elementary particles increase.
Source: http://en.wikipedia.org/wiki/Strong_interaction -
Angular momentum can apply to all objects with mass what.. although I am not too sure since I am not a physics majorOriginally posted by The return:Hiya,
I thought angular momentum only applies in mechanics? How come can applies in the behaviour of protons. I am not too good in chemistry and need to solve this doubts.
Btw the questions you asked is not chemistry but physics related
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I have one question. Since neutrons have no charge, why do we need neutrons to stabilize the nucleus?Originally posted by deathscythe99:Nuclear binding energy is the energy required to bring the constituent neutrons and protons together. The more protons u have in the entire nucleus, the more neutrons u need to stabilize it.
(Neutrons are made of protons capturing an electron BTW. Therefore, there exist interactions which it can have, mainly, electromagnetic, weak nuclear, strong nuclear and gravitational interactions)
Read here for more stuff on the atom: http://en.wikipedia.org/wiki/Atomic_nucleus
In QM model of the atom, you consider the nucleon and not the protons or neutrons. This would mean that with respect to the nucleon, u have something which has a spin and by Heisenburg's Uncertainty Principle, the smaller the vol, the greater the KE. Therefore the nucleon actually stays in shape and does not elongate or collapse. -
Let me think about it and get back to you if I still have problems.Originally posted by DriftingGuy:Forces in opposite directions cancel out one another. If an inward force is balanced by an outward force, that object is not going anywhere.
As deathscythe has explained time and time again that the electromagnetic repulsion of the protons is countered by the attractive nuclear force caused by the interactions between quarks and gluons. (within the elementary particles)
With increasing number of protons and neutrons, the electromagnetic repulsion by the increased protons increased as well. But this is again countered by the increase in nuclear force too as the number of elementary particles increase.
Source: http://en.wikipedia.org/wiki/Strong_interaction
Btw, I have one questino above. Dunno if it is a stupid question. Hope can be answered.
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Paisey to those who help me, I'm not major in chemistry nor physics. Just chance upon a question, so begin to think le.... My chemistry is very rusty.
Anyway, thanks for your help. -
I am not a physics major so i cant really answer your question. But I do know that the repulsive forces (proton electromagnetic) when balanced with nuclear force (both neutrons and protons contribute) will lead to nucleus stabilityOriginally posted by The return:Let me think about it and get back to you if I still have problems.
Btw, I have one questino above. Dunno if it is a stupid question. Hope can be answered. -
Hmm.. but how come got nuclear force contributed by both neutrons and protons? Repulsive forces I know because like charges repulse. That mysterious nuclear force comes from where? B/w +ve charge and no charge can't produce any force, if I'm not wrong.Originally posted by DriftingGuy:I am not a physics major so i cant really answer your question. But I do know that the repulsive forces (proton electromagnetic) when balanced with nuclear force (both neutrons and protons contribute) will lead to nucleus stability
This is where I get headache. Wiki only says "The nuclear force (or inter-nucleon potential) is the force between two or more nucleons. It affects the binding of nucleons into nuclei and the scattering of two nucleons. The force depends not only on the distance between two nucleons, but also on their relative velocity, and on their isospin." No says why this nuclear force will appear. -
Originally posted by deathscythe99:
Okay, after thinking a bit more and harder, I understand a bit more.
Repulsion is due to [b]electrostatic forces, these are short ranged.
Attraction, is due to the presence of strong nuclear attractive force[/b]
Ok, anyway, now I understand that neutrons are needed to stabilize the repusion inside the nucleus. ( Why are huh? )
When the protons inside the nucleus increases, we need more and more neutrons for stability right? There will come a point where no amount of neutrons can make the nuclide stable. There are just too many positive charges. Okay so we need nuclear binding energy (and angular momentum?) to really hold the protons together. And why due to the differences in neutrons no. and protons no. can produce this nuclear binding energy leh?
The in bold one are my questions. Please help.