Buck Thorn

@Mayo eg symmetry properties such as equivalence of bond lengths and angles in methane.

The original description implied that s and p orbitals have different energies. But when brought together new degenerate orbitals are evident, suggesting mixing, "hybridization".

"Can be thought of" = not necessarily real. The simple mathematical combinations of basic hydrogenic orbitals are approximations of the real orbitals. Hybridization is a word we use that implies mixing. But why mix the original hydrogenic orbitals? Yes, a perturbation would explain why. Because the description (even if approximate) that we use for individual isolated atoms no longer works when we bring the atoms into proximity of each other.

@CuckooBeats I'm not sure about that. You did the work. I visit the queues regularly as a mod and checked your work once or twice. You have been helpful with edits and that is appreciated. Otherwise I pretty much try to remain neutral and boring ;)

BTW I like bio ;) it's amazing...

@CuckooBeats His Cuckoo I was just passing through! Nice to see you're all having a good time ;)

If anyone is wondering, I removed chemistry.stackexchange.com/questions/60735/… from contention for a bounty after deciding the existing answer just required modification to include proper references. There is however a new answer worthy of a bounty.

@sanya See chemistry.stackexchange.com/questions/187494/… and other posts....

Yes, cooperativity is used somewhat loosely (as I may have) to refer to a non-linear interaction, ie enrichment in series results in a product rather than sum of individual enrichment factors. This view of cooperativity is not that different from that in hemoglobin: binding to one protein site enhances binding propensity at another.

@Sonder Granted, so your point is that what Rubisco accomplishes is not thermodynamic discimination. But if you can alter a transition (activation) energy through isotopic substitution, why not a regular binding energy (with some other protein)? This is not a question about whether such systems exist in nature (that question has been asked here before), it's about whether it's possible in principle.

@Sonder Not an expert but believe Rubisco is involved in fractionation. Either way it's a matter of principle. Photosynthesis is just a well-known example where enrichment occurs naturally. If each step enriches by a factor (however small), then cooperativity arises by chaining enrichment steps as the OP wants to do. How exactly it can be accomplished is another matter.

@Sonder plants selectively fixate (are enriched in) some isotopes more than others, which is useful in carbon dating for instance.

Cooperativity is exactly what you are looking for. "Butterfly effect" is also a non-linear effect but it is more about unpredictability, which is not what you appear interested in. Yes, you probably could do what you are interested in. You might look into the thermodynamics to establish the limiting difference in binding affinity that would allow you to discriminate two ligands after n steps.

In addition this thread deviated from the original point of your post which was bringing attention to a technical issue on your side. Unrelated questions about issues you perceive with consistency in moderation etc should have been placed into a separate post. This should probably have been brought to your attention sooner.

After the arduous back and forth I sense I understand your point. However it is not clear where or why the link to the image is broken in your browser, or why you chose to use imgur to host the image when SE has migrated to a different host and it was repeatedly explained in this thread that imgur is not supported and other methods of inserting images are available.

Uhm, yes, now I see. The imgur link does not work, indeed. Imgur is no longer hosting SE images: meta.stackexchange.com/questions/395024/…

The original post (here or in Chem SE) lacked a link, broken or otherwise: chemistry.stackexchange.com/review/first-questions/173508 . You may be unable to access the post because of permissions. A link to the post you seem to refer to is included in the edit of this meta post.

@jenny.essex I don't see the need to pester Martin with comments. You could post comments under your original question instead, and send me replies by using my handle. Bringing attention to such problems or fixing them yourself is helpful. For instance, I added a link to the Wayback Machine since the original source is broken.

Let us continue this discussion in chat.

@jenny.essex Fair enough regarding 128396. I performed the edits you suggested. I recommend you use the tools on this site more carefully. Access to them is a privilege that can be lost if they are abused.

@jenny.essex Every time you (we) post a comment here Martin automatically receives a notification. To send a notification to someone else (not the post author) use an at sign ("@") + handle ("jenny.essex").

@jenny.essex Your post here was not useful as it did make clear the source of the problem. Your original post did not provide a link (not to the broken image or anything else). I added a link to the post where the image can be found and directly to the image. Nothing is broken. What exactly are you attempting to accomplish with this post?

@jenny.essex And re chemistry.stackexchange.com/posts/128396/revisions What issues remain unaddressed? The edits there are appropriate. Proper formatting of names (conversion to lowercase), adding newlines to improve flow of text, removing unnecessary comments, all improve readability.

@jenny.essex see chemistry.meta.stackexchange.com/questions/3689/… Edits usually do not include factual corrections of content in a post unless it is somehow evident that the OP misstyped. Such edits are possible but not usually shortly after a q or a is posted. Use votes or comments to indicate your agreement with usefulness of a post, or if you seek clarification regarding its content.

@jenny.essex re chemistry.stackexchange.com/posts/185794/revisions the edits are helpful and little is missed that I can see. What would you have done different?

@jenny.essex include your comments as edits to your original meta question rather than sending repeated messages to Martin. This site is run communally. You should not target mods unless there is something important that needs to be brought to our attention. IMO your complaints which understandably you see as important seem decreasingly so in light of the effort so many others do on this site to make it better.

@jenny.essex Re chemistry.stackexchange.com/questions/185857/… what is missing in the edits? I see an image that should have been converted to text but that burden should be addressed by the OP. A message could have been left by the editor to explain this to the OP. Otherwise edits look fine.

en.wikipedia.org/wiki/Perturbation_theory_(quantum_mechanics‌​)

"Hybridization" mixes orbitals that have different energies in the original atom but the resulting hybrids are degenerate in energy. These hybrids are a form of linear combination of atomic orbitals (LCAOs), a generally useful way to represent molecular orbitals (orbitals spanning multiple atoms). Hybridization is a "quick and dirty" way of describing this. Yes, it is only useful to describe bonding, not to describe the state of an electron in an isolated atom.

Your opening paragraph seems a reasonable way of interpreting the function of models and theories. Starting from that view you need to simply decide how much to expect from this or that model or theory. To give an example, Newton's gravitational law also has clear limitations. Under certain constraints it is as accurate as more general theories.

Quantum theory is not hypothetical in the sense that it has not been tested. The theory is very robust, it has been thoroughly tested.

If you want to understand what happens as atoms approach each other look up the concept of perturbation. In essence atoms mutually alter their quantum states (single particle wavefunctions and energies). That perturbation can be said to result in mixing of the orbitals present in the isolated atoms.

I think you are "barking up the wrong tree" as they say. You are asking too much of this model. Perhaps one of your teachers or a book tried to explain how some known fact fits with the model, and went too far. Hybridization does not explain changes in any detail in the sense you propose. Other theories can describe what happens when two atoms approach each other. Hybridization is unnecessary as a model to explain states in isolated atoms and can be assumed to be complete when describing bonding.

"According to hybridisation, before bonding takes place the orbitals within the central atom combine to form a set of hybrid orbitals which all have the same energy and shape." I'm going to counter that this is likely an assumption on your part. But as with many of your questions, you have a point. Hybridization doesn't make sense without bonding.

Please post the link to the image again and I will check. No link was visible in the original post: chemistry.meta.stackexchange.com/posts/5458/revisions I don't know about "madness", but the absence of information, links or otherwise, to help the reader pinpoint the source of teh problem makes the post rather pointless.

@jenny.essex some tools behave differently for mods. However you should be receiving notifications when new comments are made on a post you started: meta.stackexchange.com/questions/125208/…

@jenny.essex Fair enough regarding 128396. I performed the edits you suggested. I recommend you use the tools on this site more carefully. Access to them is a privilege that can be lost if they are abused.

@jenny.essex Every time you (we) post a comment here Martin automatically receives a notification. To send a notification to someone else (not the post author) use an at sign ("@") + handle ("jenny.essex").

@jenny.essex Your post here was not useful as it did make clear the source of the problem. Your original post did not provide a link (not to the broken image or anything else). I added a link to the post where the image can be found and directly to the image. Nothing is broken. What exactly are you attempting to accomplish with this post?

@jenny.essex And re chemistry.stackexchange.com/posts/128396/revisions What issues remain unaddressed? The edits there are appropriate. Proper formatting of names (conversion to lowercase), adding newlines to improve flow of text, removing unnecessary comments, all improve readability.

@jenny.essex see chemistry.meta.stackexchange.com/questions/3689/… Edits usually do not include factual corrections of content in a post unless it is somehow evident that the OP misstyped. Such edits are possible but not usually shortly after a q or a is posted. Use votes or comments to indicate your agreement with usefulness of a post, or if you seek clarification regarding its content.

@jenny.essex re chemistry.stackexchange.com/posts/185794/revisions the edits are helpful and little is missed that I can see. What would you have done different?

@jenny.essex include your comments as edits to your original meta question rather than sending repeated messages to Martin. This site is run communally. You should not target mods unless there is something important that needs to be brought to our attention. IMO your complaints which understandably you see as important seem decreasingly so in light of the effort so many others do on this site to make it better.

@jenny.essex Re chemistry.stackexchange.com/questions/185857/… what is missing in the edits? I see an image that should have been converted to text but that burden should be addressed by the OP. A message could have been left by the editor to explain this to the OP. Otherwise edits look fine.

I removed an earlier comment. This seems a good question but I was confused by its rather broad scope.

Ok, I see. I guess I did not understand that point. Also, you may have missed my point. Two components (detergent and water) suffice in aqueous solution. But yes, in the case of three (including a cosolute) the cosolute will typically cause swelling but the shape will likely remain micellar at low concentrations. OTOH atoms (as in a melt) are not particularly anisotropic. But perhaps you can explain more about the structure of these so-called "micelles" in melts, composition etc.

@PaulKolk Classical surfactants possess an anisotropic structure ("polarized" or amphipathic). The micellar shape sets constraints on the shape of the surfactant. Surfactants are substances that tend to segregate to interfaces, but being a micelle implies something more and probably requires more. Perhaps getting that behaviour in a inorganic melt requires three components?

Perhaps ionic liquids are a good bridge between the systems.

How is finding a micellar system with a very high T useful when comparing an aqueous surfactant solution to a melt? Are you considering high pressure systems? Perhaps you can provide more examples or details to help clarify the point of the question.

You are trying to generalize or find parallels between systems (say aqueous surfactant solutions and mineral melts). To generalize, the question is what are properties of the system components that maximize the property in question for the types of system of interest?