Molecular Spacing of Common Items in Femtometers

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Discussion Overview

The discussion centers on the molecular spacing of various common items, including water, wood, copper, hydrogen, helium, glass (silicon dioxide), oxygen, and iron, specifically in the context of femtometers. Participants explore the atomic and molecular structures of these materials, addressing both theoretical and practical aspects of molecular spacing.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants note that copper and iron do not have well-defined molecular structures, with lattice parameters around 3 to 4 Å.
  • Glass, primarily composed of silicon dioxide, is described as amorphous, leading to typical atomic spacings ranging from 3 to 15 Å.
  • Water's molecular spacing is estimated at about 3.2 Å, but participants emphasize the significant space between molecules compared to atomic spacing within the molecules.
  • Hydrogen and helium, being gases, have intermolecular spacings that vary significantly with temperature and pressure, estimated at about 34 Å under normal temperature and pressure (NTP).
  • In wood, nearest neighbor distances can vary widely from 3 to 30 Å.
  • One participant inquires about the spacing of protons and electrons in hydrogen and helium, suggesting a need for clarification on these distances.
  • Another participant challenges the terminology used regarding "quantum levels," stating that these levels are defined by energy rather than spatial distances and requests clearer definitions.
  • Links to external resources are provided, including atomic radii for hydrogen and helium, and discussions on the proton radius and subatomic distances.
  • There is mention of the Bohr radius as a rough size for atoms, with a suggestion that nuclear components are better characterized by quantum mechanical energy states.

Areas of Agreement / Disagreement

Participants express differing views on the characterization of atomic and molecular spacing, particularly regarding the definitions of quantum levels and the relevance of spatial measurements versus energy states. The discussion remains unresolved with multiple competing perspectives presented.

Contextual Notes

Participants highlight limitations in defining molecular and atomic spacings due to the variability in states of matter (solid, liquid, gas) and the ambiguity in terminology related to quantum mechanics. There is also a noted dependence on specific conditions such as temperature and pressure for gaseous substances.

Dlockwood
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What is the molecular spacing of common items such as water, wood, copper, hydrogen, helium, glass (silicon), oxygen and iron in femtometers?
 
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Copper and iron do not have molecules. But their lattice parameters are about 3 to 4A.
Glass is mostly silicon dioxide (not silicon), which is amorphous and hence doesn't have lattice parameters. Typical atomic spacings will be from 3 to 15A, and again, you do not have well-defined molecules.

Water is a liquid with reasonably strong hydrogen bonding. An estimate from the density of water ar room temperature gives me about 3.2A as the distance between molecular centers. But since the interatomic spacing in the molecule itself is of order 1A, there really is very much more space "between" molecules as there is between atoms in a molecule.

Hydrogen and helium and gases, and their intermolecular spacing is a strong function of temperature and pressure. At NTP it is about 34A.

In wood, nearest neighbor distances can be anywhere from 3 to 30A.
 
Thank you very much. Do you know the spacing of the protons and electrons in hydrogen, and the spacing of protons, neutrons and electrons in helium?
 
Last part of question

The third and obvious part of this fourth question would be the spacing between the various quantum levels of the various elements. Probably easy for hydrogen and helium, more difficult as we go 'up the scale'. I have a theory about it but I'll wait for others to respond before I lay my ignorance on the table for others to see. I do hope to get some response from this. I'm willing to look foolish to gain more knowledge. I hope others are willing to abase themselves a little in order to expand their understanding. There is really no reason not to. If someone patronizes you or tries to denigrade you on a public forum, then just ascribe it to their arrogance and recognise that they are people of low self esteem and character. The knowledge and understanding is more important than anybody's ego. If there are people who have the answers to this question, but are bound by a secrets act, then please try not to engage in a misinformation effort. Just do us all a favor and remain silent. Hope for some response.

The reason for asking for these distances in femtometers instead of angstroms was because I thought that by the time we got to quantum levels it would easier to express these distances in whole numbers rather than decimals. It provides a common thread of measurement for all of the distances that also provides a better visual picture of these distances.

One last note for the site managers... All science has political, military and spiritual implications and ramifications. Otherwise, you would not be trying to protect secrets. Maybe you could open up a little for the benefit of everyone. Do you have a section in this forum that allows for these types of discussions? I haven't perused it in awhile so maybe I missed it.

Douglas Lockwood
530 604 5062 - cell
 
Last edited:
Dlockwood said:
The third and obvious part of this fourth question would be the spacing between the various quantum levels of the various elements.

This may be obvious to someone who knows you, but to the rest of us, it is neither obvious nor sensible in any way.

"Quantum levels" are separated in energy, not in space (at least, that is the what one usually means by a "spacing between the levels"). So, if you are using standard terminology in a non-standard manner, please provide definitions of "your terminology".
 
This may help -

Atomic radii - http://www.webelements.com/webelements/elements/text/H/radii.html
One will find atomic radii for all element. For H and He, 53 pm and 31 pm ( 1 pm = 1 picometer = 1000 femtometers), respectively. These are the effective distance between electrons and nucleus.

or alternatively - some fundamental nuclear and atomic constants

http://physics.nist.gov/cgi-bin/cuu...omic+and+nuclear.x=84&Atomic+and+nuclear.y=16

Paper on the proton 'radius' - http://arxiv.org/PS_cache/hep-ph/pdf/9712/9712347.pdf - about 0.890(14) fm, from Garching, 1997, using hydrogen Lamb shift measurements.

As the paper indicates, this is really a charge radius determined by the charge distribution inside the proton.

Pion range of strong force = 0.73 x 10 fm = 0.61 x classical proton radius.
http://hyperphysics.phy-astr.gsu.edu/hbase/forces/exchg.html#c3

Survey of scattering inside nuclei - some idea of subatomic distances - http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/scatsurv.html#c1
 
Last edited by a moderator:
Dlockwood said:
Do you know the spacing of the protons and electrons in hydrogen, and the spacing of protons, neutrons and electrons in helium?

As Gokul said, it's better to characterize electrons as having energies rather than distances from the nucleus. However, one can give a rough size for the atom, that being the Bohr radius, which is about 0.5 A. The components of nuclei (protons and neutrons) are also better expressed by quantum mechanical energy states, but the rough size is about one hundred thousandth of the Bohr radius.
 

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