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jbottle1
Hmm ok.. I see what you're saying but i'm still not completely convinced.
Since we can never know the position of the electron and its speed, things approaching the orbital will act in a way caused by the orbital of the electron. if the electron orbital was not spherical they would react in a different way. So they objects are interacting with the "sphere". I realise that the sphere is not physical but its shape still plays a role in how other things behave. If it was theoretical then it wouldn't make a difference.


The orbital is still just an area where there is a high probability of finding an electron. Even this definition is quite purposely vague. How high a probability? Usually just an arbitrarily high value like 99%.

But that still means that the electron could occupy an area outside of that sphere not to mention that other objects do not interact with the sphere (they interact with the electron) because if that always happened then we could say with 100% accuracy that the electron is simultaneously in all positions of that sphere which would violate the uncertainty principle. The fact you can experimentally crash another electron either into the nucleus or into an orbitting electron shows that the spherical orbital is just a convenient construct which makes it easier to think about the atom in physical terms.
Reply 61
jbottle1


Lol sorry you guys are probably all like degree level chemsitry so I'm sure your right but could you explain why?

Of course this is not a sphere of matter but a sphere of like force or electronegativeness or something like that haha, don't know what the proper term is.. but it is still a perfect sphere?


Nah I am doing A2 chemistry but that doesn't matter anyway.

Orbitals are just theoretical probability clouds of where you are most like to find an electron.
One electron "orbiting" a Hydrogen nucleus can theoretically be found anywhere in the universe.

Welcome to the weird world of quantum physics :biggrin:
Reply 62
I dont know if anybodys mentioned this cuz i cant be bothered to read the entire thread, but...


From a mathematical point of a view, this would be impossible. Nobody can ever create a perfect circle as Pi (3.14...) is irrational.

What people use in equations is always pretty close for what its needed for, but creating something perfectly spherical would require an absolute value of Pi...
Reply 63
Eccentric
Nah I am doing A2 chemistry but that doesn't matter anyway.

Orbitals are just theoretical probability clouds of where you are most like to find an electron.
One electron "orbiting" a Hydrogen nucleus can theoretically be found anywhere in the universe.

Welcome to the weird world of quantum physics :biggrin:


aH i see now! thanks (and also thanks to atheistwithfaith) that explains it to me! I think I kind of thought the electron was everywhere in the sphere or something lol. Cool beans
Theres alot of bad physics going on in this thread. This was by far the most intelligent post and it answer the OPs question correctly:

spread_logic_not_hate
Sub atomic particles are supposedly point-like, i.e. they are zero dimensional. This is not the same as perfectly spherical, as a sphere is a 3d geometrical object. The only perfect sphere is one that exists as an abstract mathematical object, because in reality trying to build such an object would always fail due to quantum mechanics (specifically the uncertainty principle).

The argument is as follows:

Uncertainty principle is δxδp>h2π \delta x \delta p > \frac{h}{2\pi}
where x = position of particle, p = momentum and h = Planck's constant and δ \delta is the uncertainty on these measurements.

To get a perfect sphere would require perfect placement of each atom constructing it, i.e. there could be no uncertainty on the positions of the atoms. This implies δx=0 \delta x = 0 . The uncertainty principle then requires that the momentum of the atoms constructing it is completely undefined i.e. δp= \delta p = \infty

Constructing a sphere at the atomic level would require atoms to be bound chemically together; in other words trapped in some kind of electrostatic potential well. A momentum state with infinite uncertainty can tunnel through any finite potential barrier, making it impossible to contain in practice.

This means that the act of placing a particle infinitly precisely (as is required to construct a perfect sphere) makes it physically impossible to contain this particle, meaning such a sphere would never be able to be constructed.


The problem really is that the word 'position' means different things depending on whether you use it in the context of macro scale objects or in the context of probability distributions and quantum logic.

The statement 'particles perfectly positioned(?) into the shape of a sphere' doesnt really mean anything on the quantum scale.

Speaking in the strictest of terms every particle 'exists' to some extent at every point in the universe - so you could say the only completely perfect shape that can ever exist is the same shape as the universe itself :eek:

Wesssty
Circular reasoning?


:awesome:

no. this, my friend, is... spherical reasoning!
Take it to the Physics forum, guys.

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