exchemist

Ah, I may have misinterpreted what you were looking for in terms of physical significance. Let me try another angle. You may have come across the problem with the original Rutherford-Bohr model of the atom that it can't account for why a supposedly orbiting electron does not emit radiation, lose kinetic energy and fall into the nucleus. In a sense you can view the s-orbitals as the QM version of exactly that scenario. Electrons in s orbitals have zero angular momentum, so they can't be said, in any sense, to be "orbiting " the nucleus. Instead, it is as if they continually fall towards it - even through it perhaps - and come out the other side. Being QM entities (Uncertainty Principle and all that), one cannot say they follow any defined trajectory of course, but the overall sense is of being able to touch the nucleus, rather as if they fall into it. Whereas p, d, f, etc orbitals have 1,2, 3 etc units of angular momentum and, lo and behold, all have a node at the nucleus, which is more consistent with some kind of "orbiting" motion, even though again, being QM entities, they have no defined trajectory. So I'be tempted to say the physical significance of non-zero ψ at the nucleus is a reflection of the absence of orbital angular momentum.

I don't believe there are any simple exponential processes that are relevant to this issue. Almost everything proves to be self-limiting in some way, eventually. (And actually, I've never understood the Fermi paradox. It seems to me that, given that in space travel all the numbers are awful, any intelligent race of aliens would work out that embarking on interstellar travel at all is a pointless exercise, and consequently signalling to the void is equally pointless.)

To build a bit on what @swansonthas said, yes it does have profound significance in chemistry. Because the s orbital wave function has no node at the nucleus, it implies that the electron spends some of its time up close to the nucleus. This means that, in multi-electron atoms, the s electrons are exposed to the full nuclear charge more than electrons in p , d or f orbitals, which are more "shielded" from the full nuclear charge by the electrons in shells closer in. S-orbitals are said to "penetrate" the cloud of electrons surrounding the nucleus more than the others. As one goes up* the Periodic Table, the increasing nuclear charge progressively pulls in the s orbitals and lowers their energy more than it does for the others. This is the reason why the Periodic Table has the shape it does. It results in s orbitals having lower energy than p, d or f orbitals of the same shell. This even happens to such a degree in the 4th row that at potassium, the 4s has lower energy than 3d. This is why the first row of the transition elements (d block) appears after K and Ca. It is only then that the 3d has come down in energy enough to be filled, in preference to 4p. *This concept of progressively filling subshells with electrons as the nuclear charge increases from one element to the next is known as the Aufbauprinzip (= building up principle).

While everything you have said is illuminating (to me, anyway), it presupposes an already high degree of order in living things, viz. a system of heredity, mediated by codes of bases on a long molecule. So it seems to me it can't address the fundamental argument in the (creationist) claim recited in the OP. Though I suppose it does address the issue of the probabilities involved in how more complex life arises from simple life through variation (and selection), once an RNA or DNA type replication system is up and running.

The latter: https://mecadi.com/en/literature_tools/encyclopedia/categorial/Elastomer_Thermoset/Acrylic-nitrile-Butadiene-Rubber_Buna-N_NBR

That strikes me as a rather penetrating question. +1. The answer, I think, must be that for Ca++ to pinch an electron from O-- would involve it getting a lot bigger, because the electron would have to go into the next shell (4s), which is at a greater distance from the nucleus than the 3s and 3p subshells, which are already full in Ca++. As I mentioned in an earlier post, Ca++ and O-- are of similar size and can pack efficiently. A larger Ca+ ion would pack less efficiently. The larger size would push the neighbouring ions apart, reducing the strength of the ionic bonding and leading to a higher energy state overall for the crystal. In other words, it would reduce the so-called "lattice energy".

This question is too general to be answerable as it stands. There are plenty of solvents for resins of various sorts, depending on the resin. Raw linseed oil seems a rather peculiar choice in the first place.

No.

No H⁺ cations. CO₂ reversibly forms H₂CO₃ (carbonic acid) in water, so if you can convert CO₃²⁻ to H₂CO₃, you will evolve CO₂ from the solution. That's what happens when you add acid to a carbonate solution: it fizzes. It's why acid rain erodes limestone. But without a source of H⁺, you can't form H₂CO₃.

If you are incapable of taking in the simple fact that the autopilot and MCAS are different systems, then that is your problem, not mine. Why don't you look up MCAS on the internet and find out what it is for yourself?

I think it is hard to make this claim, seeing that the period immediately after the war was an extremely fertile one for science. And, on the technology front, it is often claimed that war accelerates technology. WW2 in particular led to some rapid advances (radar, rocketry, the atom bomb...)

Thermodynamically, there is no difference. That is what we are saying. You can find innumerable ways to distinguish Man from other creatures, or to distinguish living organisms from inanimate matter. But don't look to physical science for that, which is what it looks as if you are trying to do. Physics and chemistry work the same for everything. You started this thread with a claim about random events not being able to produce order. That claim has been shown to be false, given that the universe is governed by laws that impose order. (Kinetic Theory and Statistical Thermodynamics embody the science of how randomness at the atomic scale gives rise to the ordered bulk properties of matter that we see, due to the operation of these laws. It's very interesting and mind-expanding, in my opinion, to see how that arises.) Now, you seem to be doing something a lot narrower: to find the differences between human beings and inanimate matter. That's kind of obvious, though, at one level, isn't it? I suspect you may need to rethink what it is you are really trying to do.

There is no difference, fundamentally, so you are right not to see it, I think. Schrödinger had some funny ideas in later life, as quite often happens to famous scientists. Many processes in nature involve decreases in local entropy, that is, in part of the thermodynamic system. But they are always accompanied by a greater increase in entropy in some other part of the system. For example, when water freezes, the entropy of the ice crystals is lower than liquid water, but Latent Heat is exported to the environment, increasing its entropy. Similarly, the metabolic processes of life generate waste heat. So entropy increases all the time a living organism grows. There is nothing special going on, thermodynamically speaking.

No, the opposite of random is something like "ordered" or "predictable", for example the motion of the planets. As for entropy, I think what you mean is what the Second Law of Thermodynamics predicts, which is that entropy (a measure of randomness at the atomic scale) always increases in spontaneous processes. That is just as true of life as it is of inanimate matter. If you need an explanation of how that happens, we can easily provide it.

Nobody has ever argued that the complexity of life is due to randomness alone. That's a particularly silly - and annoying -creationist representation of evolution (tornado in a junkyard etc). The complexity of life is due to natural selection operating on variations in a population. There's nothing random about selection. So we can dismiss the monkey argument as far as life is concerned. When it comes to non-living "complexity", it is unclear to me what you mean. The anthropic principle is not about complexity, so I don't really follow where your hypothetical monkeys come into it.

Like all these things it gets more complex when you delve into it. Electron affinity is the energy released by an electronegative atom when it gains an extra electron and becomes an anion. For example, all the halogens release energy on gaining an electron, meaning the anion has lower energy than the neutral atom. The same is true for oxygen when it gains one electron. However when it gains a second, that is energetically unfavourable, due to the repulsion from the net -ve charge of the anion towards a second electron. (I had forgotten this, and only remembered after looking it up.) However electron affinity is only a measure of the energy change when a free atom or ion gains an extra electron. In the case of metal oxides, the oxygen atom is not free. It is sitting in a crystal lattice, in the present case (CaO) surrounded by 6 nearest neighbour Ca2+ ions. That makes its environment much more energetically attractive for oxygen to pick up a second electron and form O2-. Hence it is common to find metal oxides with O2- anions even though, if the oxygen atom were free, you would have to "force" it to accept a second electron. (It's significant that if you put these oxides in contact with water you never get hydrated O2- ions. When they come out of the crystal lattice they pinch an H+ ion from water to make OH- (hydroxide) - plus another OH- from what is left of the water molecule: O2- +H2O -> 2OH- . As for the question about close proximity lowering potential, that's just replaying what you said, in effect, about magnets. You bring opposite magnetic poles together, or opposite electric changes together, and you lower the magnetic or electrostatic potential energy. That is reflected in the fact that you have to do work to pull them apart again. And, as they come together, magnets can gain kinetic energy, just as you said, at the expense of the magnetic potential energy. Similarly, ions with opposite charges approaching one another gain kinetic energy at the expense of electrostatic potential energy - which, in the context of molecular scale processes, means the heat energy given off in an exothermic reaction. The alkaline earth (Group II) metal oxides react with CO2 in the air, yes. I'm less sure about the alkali (Group I) metals. The carbonate anion has a charge of 2- and this means it needs 2 M+ atoms to go with it, so I'm not sure how the kinetics and thermodynamics of that work out.

There is no real distinction, though I suppose someone might - rather loosely - speak of a "vapour" until the critical point is reached, i.e. the point at which the gas/vapour can't be liquefied by application of pressure. But whether you call it vapour or gas, it is the same state of matter.

Er, I'm not asking for better example of anything. I'd like to know how the argument goes that WW1 could have been avoided if Germany had had a bigger navy. It seems to me that, seeing as France and Russia had a mutual defence pact, the war did not hinge on the UK's participation.

Yes you are right, the answer I gave before was a simplistic one, for ionic compounds generally. The case of these oxides is a bit more involved, since in fact the second electron affinity of oxygen is +ve, endothermic. The stability of compounds like CaO relies on a high lattice energy, i.e. the reduction in electrostatic potential that comes from close approach of a large number of oppositely charged ions, in a crystal lattice. In the case of CaO, the O2- anion and the Ca2+ cation are of very similar size, allowing a very efficient packing arrangement which minimises inter-ionic distances, releasing more energy, which compensates for the energy required to get a second extra electron onto the O atom. So my first answer was a bit misleading. Sorry about that.

How does that work? I would have thought the Franco-Russian Alliance would have ensured the war took place, regardless of the UK's desire to take part.

No. The reason is to do with oxidations states. Ca2+ cations are already "oxidised", in that they have a +2 oxidation state, which is the highest possible for them in normal chemistry. (Ca metal, in an oxidation state of 0, reacts vigorously with oxygen.) Another way to think of it is that CaO is comprised of Ca cations with a charge of 2+ and oxide anions with a charge of 2-. In the course of the reaction between a Ca metal atom and and an oxygen molecule, two electrons are transferred from Ca, which binds them weakly, to O which binds them strongly. This results in a net release of energy, leading to a compound has lower chemical energy than the starting materials - which is the direction all spontaneous chemical reactions take. Whereas if you try to react Ca2+ cations with oxygen, they have no more electrons to give up, so nothing happens.

Recital of this victory for England always reminds me of the curious fact that at school we learned about this battle, Crecy and Poitiers, but were never told that England lost the Hundred Years War, to France. It's one example of how history is often taught, or recollected, in a partial way, in order to bolster national myths. These national myths can have real consequences.

My son is, and I try to keep up, a bit. His main interest is the ancient world, but not exclusively so. I would certainly be interested in reading threads on that subject, anyway.

Any fool can ask questions. Providing answers that are valid is a little harder, considering that imagination does not help much with that.

In principle yes, the body's processes for regulating pH, e.g. the operation of the kidneys which transport substances against a concentration gradient, or breathing more rapidly to reduce the CO2 in the blood, can involve some energy expenditure. But only to a very minor degree and certainly not in the range it would need to be as a factor in dietary calorie control.