exchemist

Yes, I'm very rusty on this but I think you raise quite a subtle point, actually. Setting aside the electrochemistry angle, which gets in the way of the essential issue slightly, this is a general feature of the equation for Gibbs free energy, as a reaction proceeds: ΔG = ΔG⁰ + RT lnQ, Q being the reaction quotient, i.e. [products]/[reactants]. At the start, Q=0, so ln Q is undefined. Note however that this does not predict infinite Gibbs free energy or anything bonkers like that, as it is delta G i.e. dG/dξ, (using ξ to denote the reaction coordinate). So what this is saying is that the gradient of G, when graphed vs. extent of reaction, tends to infinity at the extremes. There is a discussion of this here: https://chemistry.stackexchange.com/questions/115634/calculating-Δg-at-the-extremes-of-reaction-extent/115701?noredirect=1#comment218308_115701 Returning to electrochemistry, since ΔG = -zFE, you do indeed seem to get a theoretically infinite E, at the theoretical extremes in which the activities of products or reactants are mathematically zero. In practice there are a number of catches to that, however, since firstly such extremes are never quite realised in practice and secondly in practice kinetic effects are important, e.g. in your pure water example you have virtually no ionisation to allow the electrochemical reaction to get going. But I had to think quite hard about this and I may have got it a bit wrong after all these years, so I'd quite welcome comments from others.

That does not address my query, which was about how you imagine you would generate C14, as opposed to what it decays into, which is indeed well-known. I can't find anything to suggest that irradiating C12 with neutrons will produce C14, as you seem to think it may. Where do you get that idea from?

Yes and there are antiquarks. An antiproton is composed of 3 antiquarks, for instance. So whether you consider hadrons or the quarks that make them up, it comes to the same thing: they can annihilate with the appropriate antiparticle.

I presume your idea is to generate C14, which decays to N14 by β-emission. I'm not an expert on this but I'm not sure you can readily convert C12 to C14 by neutron bombardment. Have you checked whether there is a pathway for that? (C13 is stable, I gather, so even if you could produce that it would not help.)

I do not believe anyone can identify you merely from the username “therammo”. Nothing else in this list of yours would appear to be applicable.

Read the link. It suggests an association.

Blue light from IT devices is said to be bad at bed time: . https://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side. but I don't think anyone says it is generally harmful. Some forms of blue light from LEDs contain a UV component. There are concerns that this can be harmful: https://journals.lww.com/health-physics/Fulltext/2020/05000/Light_Emitting_Diodes__LEDS___Implications_for.6.aspx But I'm not sure whether definitive conclusions have been reached as to whether the risk in commercially available LEDs is significant or not. Maybe someone here will know.

There is also the opioid crisis in the US, which I understand results in suicides. https://www.nimh.nih.gov/about/director/messages/2019/suicide-deaths-are-a-major-component-of-the-opioid-crisis-that-must-be-addressed But I can't account for the seasonality. On looking into it briefly, I am unable to substantiate what I had previously understood about a suicide peak in winter in N Europe. It may be that that is just a popular myth.

I’ve heard the same, for N Europe, I think. But that graph looks as if it may be for the US. Possibly the pressures are seasonally different there.

Hmm, interesting. I had come to suspect as much but it's nice to see it confirmed. Sometimes I will respond to a post I am a bit suspicious of, on the basis of giving the benefit of the doubt and, in the process, trying to gain evidence one way or the other. Quite often, the reaction, or lack of it, does indeed lead me to a more decisive view on the nature of the poster. It's a bit of a dilemma, though. One shouldn't react to obvious spam but there is a bit of a grey area when this type of "sleeper bot" behaviour may be occurring. (In the present case I was hoping for an amused or indignant reply, averring that the poster is real and not a bot.)

Well obviously there can't be, or cosmic expansion would have been blown up as be a failed model, long since. So it's a question of what you don't understand, rather than a contradiction in the model. But it looks as if you are in dialogue with the right people, so I'll get back to being an interested spectator.

Please note I was careful NOT to say there are no viable alternative models. I said it seems there are currently no serious alternatives. But if wavelength alters and frequency does not, then surely the speed must change. Do you want to develop a model in which c has changed over time, or something? I'm just a chemist, not a GR specialist. I've never worked with tensors. @Mordred seems to be one, however. If you are bothered that space and time are treated differently from the viewpoint of expansion you will have to listen to him.

I did wonder. The fact that the text is highlighted with a blue background indicates it has been copy-pasted from somewhere. And the poster's one previous post is similarly a little lecture that nobody had really asked for. But one can jump at shadows these days.

That's funny, you sound just like a bot. 😁

You don't say what quantitative measurement of a molecule you have in mind, so that can't be answered. One molecule is not visible to the naked eye. Incidentally, regardless of how good your eyes are, light cannot resolve objects smaller than the wavelength of the light, because it will just diffract round them instead of being reflected. The wavelength of visible light is in the range 380-750nm, whereas a single water molecule is about 0.2nm across. Taking one tsp to be 5ml, 1/8 tsp contains approx 2 x 10²² molecules. In words that is twenty thousand billion billion. There is no reason why there should not be single molecules of water floating around in all sorts of places, but we would find it very hard to detect individual molecules as they are so small. So evidence of water, which is what you ask about, generally relies on an aggregation of molecules of some kind.

Just on this small point, the relationship between speed, c, frequency, ν, and wavelength, λ, is c = νλ. This is true of any wave (light, sound, water etc). So, given that for light c is constant, as observed by us (that being the basic premise from which relativity starts), once you have said its wavelength increases there is no need to say frequency decreases: the relationship is automatic. Everyone knows this, so that's why you don't see it mentioned. I'm not sure anyone would claim that it is the only interpretation. In science one never formally closes the door to other hypotheses. Surely the claim of science is that it is the leading interpretation, to the extent that there are currently no serious alternatives? I have read about the "tired light" hypothesis for example. This was tried by some people for a while but soon blew up, as it implied predictions that were not borne out by observation.https://en.wikipedia.org/wiki/Tired_light So the reason @Genady is asking you to put forward an alternative is that there are no viable alternatives that anyone knows about, at least not at the moment.

What do you mean by help? I suppose we might be able to help you with items in your revision topics that you find difficult. Obviously nobody is going to help you cheat in the exam itself.

Google it and revert with questions if necessary. There’s no point us reinventing the wheel for you by reciting basic information that is widely available.

Word salad.

They don’t, though, do they? I thought the fusion fuel surrounded the fission fuel that sets it off.

From the responses it is clear that it is the ice that is in an approximately circular pattern, centred on the pole, which is hardly a surprise. The rock of the underlying continent is not. So nothing to do with rotation, just the amount of warmth from the sun, which obviously is at a minimum at the pole.

I don’t believe so. In the geological past, Antarctica or parts of it were at equatorial latitudes : https://discoveringantarctica.org.uk/oceans-atmosphere-landscape/ice-land-and-sea/tectonic-history-into-the-deep-freeze/

Thanks I’ve got it now, after some fat finger trouble with my ipad.