exchemist

I collect some in a water butt connected to a gutter downpipe, for watering calcifuge plants, that's all. But then I live in an area that is not short of water, as do many people. Statistics on who collects and who doesn't are only really relevant if they relate to areas that are short of water or projected to become so. As for sewage, what we need here in the UK is an initiative to separate sewage from rainwater runoff. Sewage is processed in sewage farms, not discharged to the sea (unless there's a problem with the treatment plant, which happens too often). Adding the volume of rainwater runoff to it, as we have done since the Victorian sewers were built, just magnifies the volume that has to be treated. It's a thoroughly bad idea. We ought to be able to run rainwater into the rivers and process sewage alone in the treatment plants.

This is not exactly news, though, is it? People have done this for millennia. What's the issue for discussion here?

OK I see what you mean. These nodules contain transition metal ions in low oxidation states, apparently, e.g. Mn (II).

Enlighten me.

There are micro-organisms that use sulphate to oxidise carbohydrates or hydrogen to obtain energy for their metabolism, so there are circumstances in which ΔG is -ve for a reaction scheme in which it behaves as an oxidiser, being reduced to H2S in the process. But as an oxidiser for what we would regard as a chemical fuel, not really. Concentrated (i.e. not ionised) sulphuric acid is another story however: that can be a powerful oxidising agent.

This post looks barking mad to me. A giant pot of tea? I don't see much point in attempting a serious answer to this nonsense.

In your previous thread on this subject, the possibility of organic origin was mentioned several times. If the pyrite is of organic origin, you would expect it to contain traces of other materials. If the sample is not a pure substance, you can't expect its composition to be exactly that of a pure compound. It doesn't mean there is anything "wrong" with the chemistry of the pyrite portion of it, just that there are substances present in the sample other than pyrite. I should have thought that was obvious. I don't see anything surprising here.

Sure, though that's a rather different point. Though I suppose that if the denial of abortions mainly affects ethnic minorities, that would explain why it cause huge opposition from the women. In a way the most interesting part of all this is how an issue that was originally only a Catholic position came to be adopted by evangelical Protestants as well.

They look like bits of plants or something. Considering the organic origin of these pyrites, I don't think I would find that surprising. Though difficult to confirm of course, in view of the chemical alteration involving in the fossilisation process.

That's very interesting indeed, about how the Religious Right became a political bloc. However, the way I read it, the article does not suggest the preoccupation with abortion was, or is, merely a flag to mask another agenda. It seems to say that while it was opposition to racial desegregation that originally caused the Religious Right to coalesce politically, it was actually the spike in abortions following Roe v. Wade that made it a key issue for them subsequently. So one can't infer from this article that the current preoccupation with abortion is a smokescreen disguising a racial agenda, it seems to me.

That might fit with what I was saying about an organic origin for the pyrite.

I was wondering that. If states try to make it illegal to travel to another state for abortion, I would expect that part of the state law to be challenged - in the Supreme Court! I don't see, on the face of it, how it can be acceptable to deny people the right to travel, within their own country, to take advantage of differences in law between different parts of it. Are there no precedents from other state legislation that can be cited? Drinking? Gun ownership? Age of marriage?

Jolly good. I'm not sure we ought to be offering to check all your answers, quite apart from the effort it requires (at least speaking for myself). If you've got specific queries, we can try to help with those.

Yes, undoubtedly it seems likely that phase changes play a big role, both due to latent heat effects and changes in specific volume/density.

Not as such, but there are a number of instincts that have the effect of leading to reproduction, the most obvious being the mating instinct that is the basis of sexual attraction. Another is the instinct to form partnerships with a member of the opposite sex, which is helpful for child-rearing. But of course, as we are sentient beings, there is a host of other factors that consciously or unconsciously modify our instincts, and may override them. Now that, in most societies, we can control our fertility, conscious calculations about having children play a predominant role.

OK. If the current flows between a single implanted electrode and an external ground electrode - effectively the entire skin of the subject, I suppose - then I imagine the current must radiate outward from the implanted electrode. So you will have a current density that drops off with the square of the distance from the electrode, or something like that, i.e. like the way light radiates from a point source. If on the other hand there are two implanted electrodes, the current will flow through the intervening tissue along a kind of sausage-shaped (or airship-shaped) envelope, the fatness of which will be determined by the electrical resistivity (inverse of conductivity) of the tissue - thinner if the tissue is more conductive, since more of the current can take paths close to a straight line between the electrodes. There will be a way to calculate the current density at various points between the electrodes, as a function of resistivity of the medium, but I'm afraid don't know it. Maybe someone else here will be able to help. If the electrodes are transmitting an electrical version of a sound signal (?), then there will indeed be alternating current, but involving a complex mix of frequencies. So the effect of capacitance in the tissues could be fairly hairy to model, it seems to me, as the effect will be frequency-dependent. I realise all I've been able to do is get the discussion started. We'll have to hope someone more knowledgeable shows up to take it further.

You don't say what is causing this current to flow. Do you have two electrodes, and the current flows between the two? If that's the case then if you consider blocks of the intervening tissue, they will be in series and the same current will flow through them all. Current doesn't reside in conductors. Current is a flow of electric charge, caused by a voltage gradient. A capacitor stores charge, not current. Are you considering a direct current or an alternating current? Capacitance of a conductor becomes an issue when there is alternating current. Perhaps if you can provide more details of the scenario it will be easier to make constructive comments.

Indeed. There would be no point in trying so hard, if we did not thing there was something out there, besides ourselves, to agree about.

Exactly. The whole of science is predicated on the idea that we, i.e. more than just one "self" , can agree on how something called "nature", which is external to ourselves, behaves and that we can model this nature to predict future, collectively verifiable, observations of its behaviour. I can't see how that makes any kind of sense if the only thing that exists is the self.

Interesting - something I did not know about. However from what I read, framboids are said to be composed of microscopic, even sub-micron, euhedral crystals, so they are crystalline, apparently. It seems that their formation is hypothesised to occur when pyrites form from organic matter, via greigite, Fe3S4.

The structure you have drawn for 4-nitrophenol is not quite right. You can't show 5 full bonds from nitrogen, as the n=2 valence shell has only 4 orbitals in it (s + 3x p.) It is often shown as as a resonance hybrid of a pair of structures with a double bond to one O atom and a single dative bond to the other. This gives the 2 O atoms a partial net -ve charge and the N atom a +ve charge, which is what gives the nitro group its electron-withdrawing properties on the benzene ring. Sometimes it is drawn as a mix of the 2 structures, with a single solid line to each O atom plus a dotted line to each, giving a bond order of 1 1/2 to each, for example in this Wiki article: https://en.wikipedia.org/wiki/Nitro_compound. The polarity of the nitro group, resulting from the dative bond, is crucial to understanding its influence.

Strictly speaking, doesn't this depend on what frame of reference you select? In the frame of reference of a rotating object, isn't centrifugal force real?

What do you think about the relative tendency to release H+, for these 3 molecules?

As I recall, this is all explained in some detail in the book. The whole point of that book was to work out in realistic detail what would be possible in the circumstances. Can you not get hold of a copy to read the relevant section?

That's what I fear. Musk, like most charismatic business leaders, is by temperament an autocrat. I think Trump as president again would suit him nicely.