A Speculative Model of the Atom

[lemur]

Doesn't it seem logical that electrons can't fall into the nucleus because doing so would cancel out their electrostatic charge and that would violate some conservation law? I know people hate the Bohr model and thus presumably every detail of it, but it makes sense that if an electron was orbiting the nucleus, it would accelerate the closer it came to that nucleus. This acceleration would result in greater momentum, which would function as more repellant force between electrons of different molecules when they collide. If the electron would continue to accelerating into the nucleus, it would build up momentum that couldn't be expressed as volume anymore, so it would have to be expressed as linear motion of the nucleus itself, no?

[swansont]

Doesn't it seem logical that electrons can't fall into the nucleus because doing so would cancel out their electrostatic charge and that would violate some conservation law?

 

No. Electrons do, in fact, combine with protons to form neutrons and neutrinos.

 

I know people hate the Bohr model and thus presumably every detail of it, but it makes sense that if an electron was orbiting the nucleus, it would accelerate the closer it came to that nucleus. This acceleration would result in greater momentum, which would function as more repellant force between electrons of different molecules when they collide. If the electron would continue to accelerating into the nucleus, it would build up momentum that couldn't be expressed as volume anymore, so it would have to be expressed as linear motion of the nucleus itself, no?

 

We're not talking about molecules colliding, we're talking about the electrons in an atom.

[lemur]

No. Electrons do, in fact, combine with protons to form neutrons and neutrinos.

How do the electrons collide into the protons to combine with them? Does the full energy of the electrostatic attraction from r=n to r=0 get translated into momentum of the newly formed neutron/neutrinos? This process seems like conversion of atomic volume into energy, in contrast to converting atomic mass into energy. Would that be an accurate description?

[swansont]

How do the electrons collide into the protons to combine with them?

 

It's called electron capture. It involves the weak interaction, which has a short range and thus a very small cross-section, so the reaction isn't likely.

 

e + p —> n + [imath]\nu[/imath]

 

Does the full energy of the electrostatic attraction from r=n to r=0 get translated into momentum of the newly formed neutron/neutrinos? This process seems like conversion of atomic volume into energy, in contrast to converting atomic mass into energy. Would that be an accurate description?

 

Don't know what any of that means or is supposed to mean, physics-wise, so that would be a "no."

[lemur]

Don't know what any of that means or is supposed to mean, physics-wise, so that would be a "no."

Why is this so hard to read? An attractive field results in a certain amount of KE being expressed as the two objects or particles accelerate into each other, right? Second, if electrostatic attraction is balanced by whatever keeps the electrons outside the nucleus then cancellation of the electrostatic field would result in cancelation of the volume of the atom, no? Without the positive charge of the protons and the corresponding shielding provided by the electrons, atoms would have no volume although they would have the same mass if they contained the same total number of particles, right? Thus, no mass would be converted to energy but volume would along with electrostatic force.

Edited April 15, 2011 by lemur

[swansont]

It's hard to read because energy does not get translated into momentum and atomic volume does not get converted into energy. Physics-wise, it's gibberish.

[farmboy]

How are you meant to turn volume into energy?

[lemur]

It's hard to read because energy does not get translated into momentum and atomic volume does not get converted into energy. Physics-wise, it's gibberish.

When an object is held at a certain altitude in a gravitational field, it has a certain level of potential energy, right? When that object is released into free fall, it's PE starts getting converted into momentum, so what's wrong with calling that "translation" of (potential) energy into momentum? The same could be said of chemical potential in fuel getting converted/translated into motion and heat in an engine. If energy can't be created or destroyed but only transformed, then why shouldn't stages of transformation be referred to as "translations?"

 

As for volume, what is the cause of atomic volume? In the Bohr model, I would say it was the force of the electrons as they orbit the nucleus. If you claim they don't orbit the nucleus in a classical mechanical sense, what causes them to exercise repellence toward other atoms that prevents the nuclei from getting closer to each other than they do? Whatever it is, there is a relationship between the electrostatic attraction and the volume of the atom, because without it the nucleus would presumably not be surrounded by electrons. In that case, why can't you look at the volume of the atom as an expression of force/energy and see that if there would suddenly be no electrostatic attraction, the atom would have no volume? It would have the same mass if the protons and electrons combined to form neutrons, but that mass would collapse into the nucleus, right?

Edited April 16, 2011 by lemur

[swansont]

When an object is held at a certain altitude in a gravitational field, it has a certain level of potential energy, right? When that object is released into free fall, it's PE starts getting converted into momentum, so what's wrong with calling that "translation" of (potential) energy into momentum? The same could be said of chemical potential in fuel getting converted/translated into motion and heat in an engine. If energy can't be created or destroyed but only transformed, then why shouldn't stages of transformation be referred to as "translations?"

 

Energy isn't momentum, and atoms don't behave classically.

 

As for volume, what is the cause of atomic volume? In the Bohr model, I would say it was the force of the electrons as they orbit the nucleus. If you claim they don't orbit the nucleus in a classical mechanical sense, what causes them to exercise repellence toward other atoms that prevents the nuclei from getting closer to each other than they do? Whatever it is, there is a relationship between the electrostatic attraction and the volume of the atom, because without it the nucleus would presumably not be surrounded by electrons. In that case, why can't you look at the volume of the atom as an expression of force/energy and see that if there would suddenly be no electrostatic attraction, the atom would have no volume? It would have the same mass if the protons and electrons combined to form neutrons, but that mass would collapse into the nucleus, right?

 

An atom having a volume is a separate issue of volume being an energy. Atomic size doesn't vary in the way that your idea would seem to propose, i.e. that atoms get bigger as the number of protons increase — size tends to decrease as you move across the periodic table. An isotope undergoing electron capture will often get bigger, not smaller.

[lemur]

Energy isn't momentum, and atoms don't behave classically.

So attractive force doesn't equal potential energy insofar as the particles/objects in question accelerate, thus gaining momentum? Doesn't force always mean acceleration of mass?

 

An atom having a volume is a separate issue of volume being an energy. Atomic size doesn't vary in the way that your idea would seem to propose, i.e. that atoms get bigger as the number of protons increase — size tends to decrease as you move across the periodic table. An isotope undergoing electron capture will often get bigger, not smaller.

I've sort of noticed this pattern with molecular bonding, where stronger bonds tend to be shorter. It's like the stronger the electrostatic force, the tighter the pattern between the electrons and protons in question. I wasn't saying that atomic volume was a uniform density of energy, though. I was just saying that in general it seems like the volume of the atom is due to electrostatic relations between the nucleus and electrons, as well as between electrons themselves. So if the electrons collided with the protons and neutralized their charge, that would amount to a deletion of the atomic volume and a corresponding amount of energy released in some other form, which you basically confirmed. Only for some reason, you don't want to refer to that as conversion of the atom's volume into energy, which I still don't understand why.

 

 

[farmboy]

So attractive force doesn't equal potential energy insofar as the particles/objects in question accelerate, thus gaining momentum? Doesn't force always mean acceleration of mass?

 

 

I've sort of noticed this pattern with molecular bonding, where stronger bonds tend to be shorter. It's like the stronger the electrostatic force, the tighter the pattern between the electrons and protons in question. I wasn't saying that atomic volume was a uniform density of energy, though. I was just saying that in general it seems like the volume of the atom is due to electrostatic relations between the nucleus and electrons, as well as between electrons themselves. So if the electrons collided with the protons and neutralized their charge, that would amount to a deletion of the atomic volume and a corresponding amount of energy released in some other form, which you basically confirmed. Only for some reason, you don't want to refer to that as conversion of the atom's volume into energy, which I still don't understand why.

 

He probably doesn't want to say that, because that isn't what is happening dude. Volume isn't being transformed into energy. The change in volume (assuming that even does happen) is just coincidental, not the actual cause of energy transfer.

[lemur]

He probably doesn't want to say that, because that isn't what is happening dude. Volume isn't being transformed into energy. The change in volume (assuming that even does happen) is just coincidental, not the actual cause of energy transfer.

I don't know what you mean by it being the cause. What is it that generates volume in the atom and how? Then what happens when the electron(s) collapse into the nucleus and why is energy released as a result?

[farmboy]

I don't know what you mean by it being the cause. What is it that generates volume in the atom and how? Then what happens when the electron(s) collapse into the nucleus and why is energy released as a result?

 

Because you have an electron which has energy assosciated with it, then if it interacts with the nucleus you no longer have an electron and so the energy assosciated with it is transfered into other forms. The energy transformation is real, it just has nothing to do with converting volume into energy since volume isn't a type of energy.

[swansont]

So attractive force doesn't equal potential energy insofar as the particles/objects in question accelerate, thus gaining momentum? Doesn't force always mean acceleration of mass?

 

Conservative attractive forces give rise to potential energy, but are never equal to it. Accelerating particles can gain or lose momentum, depending on the direction of the acceleration, but these (and energy and force) are all separate terms and cannot be equated.

 

Only for some reason, you don't want to refer to that as conversion of the atom's volume into energy, which I still don't understand why.

 

Because it's wrong. Flawed models give wrong answers. You don't go forward and apply them, you fix the problems with them and come up with a better model.

[lemur]

Because you have an electron which has energy assosciated with it, then if it interacts with the nucleus you no longer have an electron and so the energy assosciated with it is transfered into other forms. The energy transformation is real, it just has nothing to do with converting volume into energy since volume isn't a type of energy.

Volume isn't a type of energy? It's a function of energy, isn't it? Atoms aren't solid "matter," are they (whatever that would mean)?

 

Conservative attractive forces give rise to potential energy, but are never equal to it. Accelerating particles can gain or lose momentum, depending on the direction of the acceleration, but these (and energy and force) are all separate terms and cannot be equated.

I don't understand. When I think of an attractive field, i think of every trajectory through it in any direction resulting in increases and decreases of potential energy as it is exchange for kinetic energy and vice versa. How can two things attracted to each other lose distance without an increase in kinetic energy that is conserved in whatever forms it is converted?

 

Because it's wrong. Flawed models give wrong answers. You don't go forward and apply them, you fix the problems with them and come up with a better model.

It's not a predictive model. It is an analytical summary description. It is like saying that coal is a conversion of gravitational force into carbohydrate concentration or that sugar beets are a conversion of sunlight into carbohydrates or like saying that fission/fusion is a conversion of mass into energy or fire is a conversion of chemical potential into heat. Is it incorrect in comparison with these?

 

 

[swansont]

Volume isn't a type of energy? It's a function of energy, isn't it? Atoms aren't solid "matter," are they (whatever that would mean)?

 

No, it's not a type of energy.

 

I don't understand. When I think of an attractive field, i think of every trajectory through it in any direction resulting in increases and decreases of potential energy as it is exchange for kinetic energy and vice versa. How can two things attracted to each other lose distance without an increase in kinetic energy that is conserved in whatever forms it is converted?

 

This example uses kinetic and potential energy. That's fine — those are two forms of energy. Meanwhile, force, acceleration and momentum are still distinct concepts.

 

It's not a predictive model. It is an analytical summary description.

 

An incorrect analytical summary description.

[michel123456]

No, it's not a type of energy.

 

I understand Lemur.

 

If you take a macroscopic object made of a huge amount of atoms, and heat it, the object generally will expand (except for water). If you take energy out by reducing the temperature, the object will contract. In this view volume is related to energy. Isn't it the same at the atomic level?

[farmboy]

I understand Lemur.

 

If you take a macroscopic object made of a huge amount of atoms, and heat it, the object generally will expand (except for water). If you take energy out by reducing the temperature, the object will contract. In this view volume is related to energy. Isn't it the same at the atomic level?

 

Hmm, when you heat something and cause it to expand it isn't the atoms themselves which increase in size, just the distances between them. Is that what you meant pal, or have I missed the point lol. Now with atoms I don't think there is a direct correlation between energy and atomic size. For example lithium has a significantly greater atomic radius than fluorine (1.52A vs. 0.62A) even though fluorine contains more electrons at higher enrgy levels (I think the configuration are Li 1s² 2s¹ and fluorine 1s² 2s² 2p⁵) so I think (though im really not positive) that if volume were a type of energy first off you would see an increased volume corresponding to the increased electron energy levels and you would see the same effect if volume were directly correlated to energy levels in the electrons.

[swansont]

I understand Lemur.

 

If you take a macroscopic object made of a huge amount of atoms, and heat it, the object generally will expand (except for water). If you take energy out by reducing the temperature, the object will contract. In this view volume is related to energy. Isn't it the same at the atomic level?

 

The question one must answer is what makes the energy related to volume in this case. Is it something intrinsic to volume, i.e. larger volumes always have more energy? No. Volume appears in the energy term for an ideal gas, but it's multiplied by pressure. And you can work back from that and see that the pressure can be related to the work the gases can do in colliding against a surface; what's important there is the amount of surface area and how often the collisions occur — which, for atoms of a given speed, is inversely related to the characteristic diameter (or length) of the enclosing surface. That length, multiplied by the surface area gives a volume term. But you miss all that if you take a shortcut and think that the volume is energy. You get lucky if you have a system at constant pressure — then the energy is directly proportional to the volume. If you try and apply it elsewhere, you get flat-out incorrect results.

[lemur]

I understand Lemur.

 

If you take a macroscopic object made of a huge amount of atoms, and heat it, the object generally will expand (except for water). If you take energy out by reducing the temperature, the object will contract. In this view volume is related to energy. Isn't it the same at the atomic level?

Thanks, Michel, for getting this at the basic level that I meant it. The gas comparison seems to be relevant in so many cases of electron behavior. This is conform with what I read in Planck's book "Survey of Physical Theory," where he writes that electricity will ultimately be studied like a gas in terms of gas laws and thermodynamics, etc. This has already made sense to me in terms of energy transmission through a conductor, including sound waves. So why shouldn't this same ana-logic be applied to the electron's relationship with volume around the nucleus?

 

I haven't dismissed what Swanson and others are writing. I see that there's no simple relationship between atomic volume and energy, as with pressure and heat with a gas, etc. I also still haven't figured out a simple way to think about the relationship between positive charge-attraction and volume-producing electron energy without treating the electrons like gas particles surrounding the nucleus. Nevertheless, I could imagine explaining things like ductility vs. crystal rigidity in terms of "pressure rigidity" if atoms were viewed like little balloons with variable size and pressure/rigidity.

[insane_alien]

because when considering many billions of electrons you probably CAN make an analogy to various other systems as everything smoothes out. but on a quantum scale you can't really say the same.

 

think of it like organising a very large multiple choice game. you can probably predict with a good degree of accuracy what percentage of players will pick a certain answer assuming oyu have a large ie >1000 number of players. but you could not predict what a single player would pick based on the same methods.

[michel123456]

I always wondered why there is no model of collapsing atom. Why do all models have to be in a state of equilibrium?

 

If the atom was indeed collapsing, and since we are made of atoms, why not? That's all relative.

[farmboy]

Thanks, Michel, for getting this at the basic level that I meant it. The gas comparison seems to be relevant in so many cases of electron behavior. This is conform with what I read in Planck's book "Survey of Physical Theory," where he writes that electricity will ultimately be studied like a gas in terms of gas laws and thermodynamics, etc. This has already made sense to me in terms of energy transmission through a conductor, including sound waves. So why shouldn't this same ana-logic be applied to the electron's relationship with volume around the nucleus?

 

I haven't dismissed what Swanson and others are writing. I see that there's no simple relationship between atomic volume and energy, as with pressure and heat with a gas, etc. I also still haven't figured out a simple way to think about the relationship between positive charge-attraction and volume-producing electron energy without treating the electrons like gas particles surrounding the nucleus. Nevertheless, I could imagine explaining things like ductility vs. crystal rigidity in terms of "pressure rigidity" if atoms were viewed like little balloons with variable size and pressure/rigidity.

 

 

Atoms aren't like little baloons with variable pressure/rigidity though pal. Within a lattice, atomic radii are not variable (in that they don't change not that there aren't different radii within a lattice), there are many techniques we can use now which show that the actual size or shape of different atoms does not change based on how the material at large is manipulated (this only happens through chemical processes). So for example the way you are talking about it, stretching out a certain ductile material would actually deform the electron cloud of the atoms which make it up accounting for the change in shape of the material overall. That doesn't happen though, the change in shape is already perfectly explained by looking at the way the atoms move relative to one another. This is quite a big area of chemistry, but basically the properties of different lattices is dependant on the atoms which make it up (is it pure or a mixture) and what configuration the lattice takes on, the type of bonding present etc. The electron clouds aren't actually deformed in any way.

Edited April 17, 2011 by farmboy

[swansont]

Thanks, Michel, for getting this at the basic level that I meant it. The gas comparison seems to be relevant in so many cases of electron behavior. This is conform with what I read in Planck's book "Survey of Physical Theory," where he writes that electricity will ultimately be studied like a gas in terms of gas laws and thermodynamics, etc. This has already made sense to me in terms of energy transmission through a conductor, including sound waves. So why shouldn't this same ana-logic be applied to the electron's relationship with volume around the nucleus?

 

Because electricity and behavior of atomic electrons are separate subjects. Go ahead and try to model an atom as a thermodynamic system, but you have to show that it works before you can actually apply it anywhere.

[lemur]

Atoms aren't like little baloons with variable pressure/rigidity though pal. Within a lattice, atomic radii are not variable (in that they don't change not that there aren't different radii within a lattice), there are many techniques we can use now which show that the actual size or shape of different atoms does not change based on how the material at large is manipulated (this only happens through chemical processes). So for example the way you are talking about it, stretching out a certain ductile material would actually deform the electron cloud of the atoms which make it up accounting for the change in shape of the material overall. That doesn't happen though, the change in shape is already perfectly explained by looking at the way the atoms move relative to one another. This is quite a big area of chemistry, but basically the properties of different lattices is dependant on the atoms which make it up (is it pure or a mixture) and what configuration the lattice takes on, the type of bonding present etc. The electron clouds aren't actually deformed in any way.

I am interested in what information allows you to exclude all the things you exclude at the beginning of this post. Are the methods of imaging individual atoms in dynamic situations really good enough to allow them to be observed under pertinent conditions? Assuming that you are positive about behavior like ductility emerging from the lattice relations and the characteristics of the atoms that determine their particular latticing tendencies, could you please explain in a concrete example how this works? I.e. pick a particular metal and explain its ductility in terms of its latticing tendencies and how these tendencies are determined at the atomic level.