

exchemist
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No material can have a net negative charge. [Answered: Wrong!]
exchemist replied to martillo's topic in Speculations
To remove the electron from a hydrogen atom you have to ionise it. This take a a lot of energy and does not happen until very high temperatures are reached, enough to turn hydrogen into a plasma. The ionisation energy is known: ~1300kJ/mol or ~13eV. So what you say is wrong. It is true that you get release of electrons from a metal when you heat it enough, via thermionic emission. This requires overcoming the work function for the material, for many metals of the order of 4eV. This is a lot less than the ionisation energy of hydrogen, but still high enough to require a significantly high temperature. Note that overcoming the work function is ionisation of only the topmost, tiny fraction of the most loosely bound electrons in a metallic bonding system, so it is far lower than the ionisation energy for an individual atom. Furthermore, what you say about the chlorine atom is also wrong. A neutral Cl atom has an electron affinity of ~350kJ/mol, which means that much energy is released when it captures an extra electron, i.e. the Cl- anion is more stable than the neutral atom. This anion has a net -ve charge of -1. Please stop confusing the photoelectric effect with thermal ionisation. They are quite different. Thermal ionisation requires electrons to be knocked out of the valence shell of the atom by collisions with other atoms or molecules. The photoelectric effect is due to absorption of radiation. As for the rest of what you say, it would really help if you could confine yourself to one wrong statement per post. 😆 -
No. This looks like mad ballocks.
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I'm not sure there is anything new here. We all knew Trump would pretend the early Republican lead, and subsequent erosion of it by postal ballots, would be a sign of election-rigging. We also all know Bannon has wanted for years to bring down the whole structure and that he revels in the prospect of chaos and right wing dictatorship. Bannon is a nutter.
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Yes @Halc has pinpointed the flaw in your analysis. You have omitted the torque that is also exerted at your "point of application of the repulsive force". This will be a clockwise torque. Alternatively, taking your brown construction as a rigid body, it should be obvious that applying two opposite forces (whether from magnets or anything else) along the diameter will simply tend to squeeze it and will not cause any rotation, regardless of its shape.
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What's wrong with you? In the time you have spent asking about this perfectly simple procedure, you could have already done it several times over. Just tip it in and stir it up. Use a glass container, so you see when all the crystals have disappeared from the bottom.
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Reverse Sonoluminescence
exchemist replied to Beasleybawss's topic in Modern and Theoretical Physics
Ah. Soot is a very black and therefore good absorber of radiation, converting it to heat. What may be happening is the soot layer may be warming and expanding and moving on the glass surface via a stick-slip process. -
Reverse Sonoluminescence
exchemist replied to Beasleybawss's topic in Modern and Theoretical Physics
If you tell us what you have done, or found out, some of us might be intrigued. But if you are going be all coy about it we will lose interest rapidly. -
How can there be a wide range of current flow?
exchemist replied to Tim Barber's topic in Other Sciences
Oh that's easy. There are ~6.25 x 10¹⁸ electrons in one Coulomb of electric charge and 1 amp = 1 Coulomb/sec. You can find estimates on the internet for the current in amps in a lightning discharge. Bear in mind that, as current is a rate of flow of charge, you can get very high currents without necessarily transferring enormous amounts of charge, if that current only flows for a fraction of a second. -
How can there be a wide range of current flow?
exchemist replied to Tim Barber's topic in Other Sciences
In an electric current, the electrons move through the conductor very slowly, not at the speed of light. As I understand it, what moves fast through a conductor is any signal, i.e. any change to the rate of flow at one end propagates very fast to the other end, because the electrons in between can be though of as essentially incompressible. Since current is a measure of the charge passing a given point per unit time, e.g, amps = Coulombs/sec, a greater current can be achieved by more electrons moving, as well as by a greater speed of motion. But some of the physicists here may be able to explain better than I can. -
John, if you are a student, as you represented yourself as being earlier, the first rule is RTFQ, Read The ----ing Question. This thread is about interpreting NMR spectra. But I'm wondering now if you are a 'bot, because of your inane suggestion that you can analyse a spectrum by wet chemistry methods.
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Dynamic Gravity theory to explain dark matter, cosmic ray energy, etc.
exchemist replied to kba's topic in Speculations
Yes, fair enough, that makes sense, in the wave picture at any rate. -
Dynamic Gravity theory to explain dark matter, cosmic ray energy, etc.
exchemist replied to kba's topic in Speculations
Are you trying to tell me that electrons in an atomic or molecular orbital have kinetic energy without motion? How does that work? -
English Language - words, meanings and context
exchemist replied to Intoscience's topic in The Lounge
I remember realising that all these places with "wick" in them are also found in the Netherlands "wijk". I think it comes from the Vikings. I wish I knew some North East dialect. It is, or can be, a lovely accent. This YouTuber, Charlotte, for instance is someone I can listen to all day (County Durham, I think she is?): Listening to her I suddenly recalled, from 60 years ago, a Geordie folk song my mother used to sing when we were small: "The Keel Row". Perhaps you know it. -
English Language - words, meanings and context
exchemist replied to Intoscience's topic in The Lounge
I don't think it makes any sense to tinker with language in this way. All languages have strange things in them. It's part of their charm and reflects their convoluted history. To try to remove them all would be to lose all that richness - and deprive writers and poets of the opportunity for puns and deliberate ambiguities. Take a word like "mine". That can mean either an excavation in the earth for minerals or a static explosive armament. But in fact they have a common origin. The original explosive mine was gunpowder placed at the end of an excavated shaft, dug to blow up (undermine) the walls of a castle. Hamlet speaks of "the engineer hoist with his own petard" (a synonym for mine) and goes on to say "but I shall delve one yard below their mine and blow them at the moon".* I think discovering the common root of these things is fun. And then we have different spellings and meanings for the same sounding word: rite, write, right, wright. English has more of this sort of thing than most languages, because it draws on both Germanic and Latin roots, forming in effect two vocabularies. Historically the upper classes spoke (Norman) French and used Latin-derived words, while the peasants used an Anglo-Saxon vocabulary. To this day the Germanic words sound more "earthy" and less refined than the Latin-based equivalents. This was brought home to me in the Netherlands, when I was sent for a blood test, at the "prikpost". I understood what it meant, but it sounded a bit, well, blunt. So I'm in favour of leaving these things alone and enjoying the diversity. * If you visit St Andrew's, in Scotland, there is a ruined castle where you can see both such a mine, dug during a seige, and a "countermine", dug from inside the castle to stop it. You can go through, down a ladder, from one to the other, at the point where they meet. -
Dynamic Gravity theory to explain dark matter, cosmic ray energy, etc.
exchemist replied to kba's topic in Speculations
Not appreciably, though. That's why I qualified my statement by including that word. As for QM, I don't follow you. Schrödinger's equation is based on electrons possessing kinetic, as well as potential, energy, is it not? So movement seems to be implied, even if trajectories cannot be defined. Furthermore in heavy atoms, my understanding is that one has to make relativistic corrections to allow for the "speed" of the electrons becoming a significant fraction of c, which makes the orbitals more stable than would otherwise be the case (e.g. why Hg is liquid, why Au is yellow, etc.) -
Dynamic Gravity theory to explain dark matter, cosmic ray energy, etc.
exchemist replied to kba's topic in Speculations
But if that were so, things would get appreciably heavier when they became warmer or entered excited states. We don't observe that, do we? -
Dynamic Gravity theory to explain dark matter, cosmic ray energy, etc.
exchemist replied to kba's topic in Speculations
How do you explain the weight of a lump of concrete? -
You will find the number of moles is a suspiciously convenient number....... But your residue is a mixture of oxides: BaO and XO. (You are told it involves XCO3, not X2CO3 or X2(CO3)3 or something, so X has to be divalent and presumably produces an oxide with formula XO.) You now know how many moles of X you have but not how many of Ba, yet. That's where the acid reaction comes in, I think. I have not worked it through myself but, looking at the problem, I think that's what you are supposed to use to find the answer. Good luck.
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This is too mad to be worthy of a serious response.
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How many moles of CO2 are driven off?
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And I speculate that you are just pulling random stuff out of your arse in a bid for attention😁.
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The earth’s core (split from Does our moon affect Earth's core)
exchemist replied to Luzephyr's topic in Earth Science
There is plenty of information about this on the internet, if you are genuinely interested (which I am not convinced you are, since if you were you would already have read it). There is no reason for people here to duplicate it. I suggest you read the portion of this Wiki article that relates to the Earth's core first: https://en.wikipedia.org/wiki/Structure_of_Earth#Core , and then revert with any specific issues you may want to discuss. -
Oh, maybe I misunderstood. Pumped storage hydro is well established: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity Do you mean doing this at the level of the individual household, then? Have you done the calculation on what weight of water you need for a battery of adequate size? I have a feeling it might be rather large. But if you can give an idea of how many kWh storage would be needed, we can do the maths. P.S. Lifting 1mt through 1m gives you 10kJ, so if we take a 10 m high building, that would be 100kJ. Storage of 1kWh would require 3600kJ to be stored, i.e. 36mt water. That would require quite a structure to support it.
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I think I made something new but I have no idea.
exchemist replied to somerandomname's topic in Inorganic Chemistry
Bleach is a terrible choice if you're just wanting a weak base, as it is highly reactive in its own right and can evolve poisonous gas (Cl2). A good weak base is something like baking soda, NaHCO3. That will fizz and evolve CO2 in contact with an acid, but all it does to what remains is to introduce some Na+ ions. What intrigues me about the reaction is the possibility of producing some elemental sulphur. That will be insoluble in aqueous solution so you should get some kind of yellow precipitate if you let it all settle.