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exchemist

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exchemist last won the day on January 14

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  • Location
    London
  • Interests
    Rowing, choral singing, walking.
  • College Major/Degree
    Chemistry MA, Oxford
  • Favorite Area of Science
    chemistry
  • Biography
    Trained as a patent agent, then gave it up and worked for Shell, in the lubricants business for 33 years. Widowed, with one teenage son.
  • Occupation
    Retired

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  1. No they can’t. These are 3D standing wave patterns, similar to the “spherical harmonics” you can excite by striking a rubber ball and watching its deformation with a stroboscope: And relying on AI in the way you are trying to is going to lead you astray. Don’t outsource your understanding to a bot.
  2. Blimey! So the vent pipe was dipping into the water in the header tank. How weird. So you would have had cold water being sucked down the vent pipe when you ran hot water off. Not a great piece of plumbing, by the sound of it. But now I see why it had the effect it had. Comforting to know the cylinder can pop back into shape rather than splitting at the seams, at any rate. 🙂
  3. This is a bit silly. Musk would have better things to do than try to take down videos making outlandish claims on his behalf, even if he were a person interested in truthfulness (which he is not, I agree). You can’t blame him for crap posted by other people. But you posted these videos, here on this forum, as evidence Musk was making false claims about warp drive and an anti- gravity fighter aircraft. So you took them at face value, without checking. That is not very sensible. Before responding to your post, I made a quick search for any claims involving Musk and either warp drive or anti- gravity…….and found nothing at all. So it seems to be BS.
  4. That’s odd. Was the hot water cylinder not vented? I thought that was a requirement, e.g. a riser off the main hot water exit at the top of the cylinder. If it had been, there would have been no vacuum created. (I went into this once, worrying about whether I could change a tap washer on a hot tap in my house, after turning off the cold water feed to the cylinder. I eventually convinced myself I could not collapse the cylinder, because of the vent pipe.)
  5. What makes you think these videos were posted by Musk? YouTube is full of all sorts of shit.
  6. That article is poorly written. The term “orbital” was devised precisely because electrons in an atom do not have definite orbits. This is due to their wavelike nature or, to put it another way, to the uncertainty principle. On the more general issue of this modelling attempt of yours, I have difficulty seeing what it is for. You initially referred to gravity, but this seems to be some kind of attempt to reproduce the effect of electromagnetic interactions between atoms. Which is it?
  7. You can't get round the solubility of a substance in a given solvent in this way. It is what it is. If this substance is water-soluble, it is likely it has some degree of solubility in an ethanol/propylene glycol mixture, as both are also polar solvents. But the solubility may be a great deal lower- as you have evidently discovered. As for additives, surfactants can sometimes be used to create emulsions, i.e. to suspend rather than dissolve the insoluble material. This is how detergents work to remove grease and oil, for instance, which are not water-soluble. Maybe if you can explain what you are trying to do in more detail, somebody may be able to advise you further.
  8. It seems you are unaware of the principle of induction furnaces: https://en.wikipedia.org/wiki/Induction_furnace
  9. Yes. And warm water is even better. Warm water can help unfreeze freeze water in your pipes. Because it's warm, you see. 🤪
  10. I should think it must be. I would expect this layout, with the oesophagus behind the lungs, to be common to all tetrapods. But I'm not a biologist.
  11. I feel sure the extra sugar in the US is in large part due to the decades-long inculcation of the "coca cola culture" which has, through incessant lifestyle marketing, habituated the US palate to sweetness. Drinking sweet beverages with a meal seems to be normal. In France that would be thought barbaric - and ultimately of course it can be bariatric 😄. I recall a US colleague, on a visit to our Hamburg office, expressing astonishment, almost to the point of panic, that there was no soft drink dispenser. Coffee there was of course, but he seemed to need his coca cola.
  12. Yes it can be confusing. Notice these groups are described as Main Groups, and also that the block in between (often called the d-block) is described as being for the Transition Metals. The "transition" metals were historically viewed as being in the transition from the simpler rules of chemical behaviour of the light elements of the 1st 3 rows to the more complex behaviour of the heavier ones from the 4th row onward. (As with so many things in science, history has a lot to do with how things end up being named.) Nowadays, it is really better to speak of the s-block, for the 1st 2 main groups, the p-block for groups 3-7 and 0, the d-block for the transition metals (and the f-block for the so-called lanthanides and actinides that are usually represented below the d-block.) But over the years there have been many different ways to display the table and also a variety of different numbering systems and naming conventions. So inevitably you will come across a few different ones in your reading. Just keep the shape in your mind: 2 columns of s-block metals on the left, 6 columns of p-block elements on the right, with the metal/non-metal diagonal running obliquely through them like a staircase, and the d- and f- block metals in the middle. The reason for the rather ungainly shape of the table is to do with the order in which electrons build up* in layers within the atom, as one moves through the table from lighter elements to heavier ones. Remember that It is the outer electrons (called the "valence" electrons) that are responsible for the chemical behaviour of the elements. The shape of the outermost layer, and how strongly or weakly bound the electrons in it are, is what determines how the element will behave in chemical reactions. * from the German Aufbauprinzip or building up principle, which explains how the behaviour of the outermost electrons is determined by quantum theory. You will get to that in due course. It's rather cool.
  13. Yes, your writing is atrocious - and long-winded. Can you try again, this time writing no more than a couple of short paragraphs and in complete sentences, i.e. using full stops? At the moment I find myself giving up trying to work out what you are trying to say after about 6 lines.
  14. Don’t be an idiot.
  15. I think you may be confusing abstract mathematics with physics. Calculus is used all the time in QM. The uncertainty principle arises from pairs of non-commuting operators for certain observable properties. This concept is quite compatible with calculus. In fact some of the operators concerned contain things like derivatives.
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