exchemist

Actually not that much becomes converted to ammonium and hydroxide. Most of it is still NH3(aq) : https://en.wikipedia.org/wiki/Ammonia_solution As I recall, ammonia is not much of a reducing agent as it can't give up electrons easily, only share them in a covalent bond, as in H3N:->H+ . (If it actually reduced H+, hydrogen would be evolved.) But yeah it's easy to get in a muddle with Lewis acids and bases. It's one of those concepts I tended to dodge, not finding it awfully helpful on most occasions. No I don't think so. Sugars have hydroxy groups on them that can be protonated in acid conditions, i.e. R-OH + H⁺ <-> R-OH₂⁺ , but they are no more liable to be protonated than a water molecule, i.e. H₂O + H⁺ <->H₃O⁺, so that won't raise the pH. (While sweet substances make acidic substances taste less acid, they do not do so by neutralising the acidity. It's just a trick of the taste buds.)

Not necessarily. For example, some cations form complexes with OH-, thereby causing water to release H+, acidifiying the solution. Both in the case of ammonia and in the case of metal cations such as Al 3+, water is caused to split, by abstracting either H+ in the case of ammonia or OH- in the case of Al 3+, leaving behind extra OH- or H+ respectively and thus altering the pH of the solution.

Think of ammonia. It does not dissociate appreciably in solution but accepts H+, causing water to dissociate, and thereby raises pH. Stomach acid has a pH ~2, so has plenty of free H+. I can't see why this would in itself cause other substances to dissociate, though protein dissociation is catalysed by enzymes in the acid environment of the stomach, I believe.

All you are saying is that science is a method which, like many things, is an abstract concept. Nobody would deny the usefulness of abstract concepts. Mathematics is abstract, and you can't do some sciences at all to any degree without maths. What you are demanding seems to be something different: the existence, not of an abstract concept but of an extra dimension. This implies that objects can be situated along this dimension and assigned intervals, relative to one another, in terms of it, by some kind of measurement.

Do you think distance is unobservable then? After all, all we can measure is distance intervals. Also consider that with something like energy, all we can measure is energy differences, which are a kind of interval too.

On what grounds do you demand recognition, from physicalists, of something for which there is no observational evidence? Surely you understand that for the physicalist, unobservable entities are dismissed as non-existent?

I'm certainly not going to use that Philadelphia stuff. 😝 I'm going to use a hard cheese with some flavour. But that picture looks as if it may be sweet cassava flour (polvilho doce - doce may mean sweet, like dolce.) As I say, I have a recipe. All I need is to source the right kind of cassava flour. The recipe calls for sour not sweet (polvilho azedo). I'm going to ask my cleaner to get me some, from the Brazilian shop close to where she lives in Streatham. If it works, I may post it for comparison. The key thing will be to get that special chewy texture that you can't get with wheat flour. They are nice with a cup of tea, in the afternoon, as an alternative to the cheese scones I sometimes make.

As far as I can tell it seems to be the same stuff, basically. There seem to be two versions of cassava flour, sweet and sour, the latter being fermented before final preparation. I am interested in this as I want to make pan de queijo, which one of my son's Brazilian nannies/babysitters used to make and which I found delicious. I now have a Brazilian cleaner who brings me some occasionally but she doesn't make it herself and it is not quite as good. Cassava flour is not easy to find in London, though there are Brazilian shops where one can get it. I have a recipe that I found on line that calls for sour cassava flour.

Disappearance of the major component of the tides, with a devastating effect on intertidal organisms and probably other ecosystems that benefit from the flushing action of tides.

Me for a start. What did you mean by suggesting he might (rhetorically) have a gun to the back of his head? What a needlessly aggressive and uninformative remark. And then you made a further ridiculous statement about it being naïve to think taxes and tariffs can "solve" problems. Nobody suggests they "solve" anything of course. Alternatively, to deny that taxes and tariffs can play a role, by modifying the behaviour of commercial enterprises, if that is what you meant to say, would be equally absurd. In this case there is a particularly strong case for taxes and tariffs, since one of the great problems in addressing climate change is the lack of any direct market-based feedback between the products (and their pricing) available to consumers and the resulting costs down the road for us all due to climate change. So, all in all, a fairly poor post from you, I thought.

The problem, as @chenbeier says, is that a carbonyl group will react with a Grignard reagent much faster than a carboxylate. So any acetophenone produced would immediately react in preference to the remaining carboxylate. I’m not sure whether a carboxylate anion will react at all with a Grignard reagent. Nucleophilic attack on an anion seems like a bit of an uphill struggle, though it’s true most of the -ve charge will be on the O atoms.

Carboxylate anions are not very strongly electrophilic, if I remember correctly. What do you think will happen? Something has gone wrong with your post.

What I meant is that it is a bit of a stretch to claim the Holy Roman Emperors represent a continuation of the Western Roman Empire. They were not Romans, they ruled over various chunks of continental Western Europe, and did so from places nowhere near Rome, like Aachen.

Defying Hitler. Synopsis: "Sebastian Haffner was a non-Jewish German who emigrated to England in 1938. This memoir (written in 1939 but only published now for the first time) begins in 1914 when the family summer holiday is cut short by the outbreak of war, and ends with Hitler's assumption of power in 1933. It is a portrait of himself and his own generation in Germany, those born between 1900 and 1910, and brilliantly explains through his own experiences and those of his friends how that generation came to be seduced by Hitler and Nazism." I thought now would be a good time to read how a demagogue, encouraging a cult of personality, can subvert the institutions of the state and seduce a population, little by little.

Sorry typo thanks.

Yes but the Holy Roman Emperor was just an honorary title that developed from the coronation of Charlemagne as emperor by the pope, in return for the protection he provided to Rome against the Lombards etc. Whereas the Roman Empire in the East survived in Constantinople until 1543.

I don't think so. The basic problem, as I understand it, was over-extension of the Empire and consequently increasing reliance of the army on colonised people to man it. I think competition from the Goths, notably Alaric, had something to do with it as well. But that was not until c.4th AD. I think it was still flourishing in the c.1st.

Sounds good in principle but I can't help wondering how the industries affected are going to calculate the numbers to submit on imported goods, and how the EU will be able to check they are genuine.

No. The pairing is dictated by the way the H bonds line up and this makes only 2 specific pairs fit together, namely A-T and G-C. This is what ensures that a single strand of DNA, when it has been unzipped, will attract the same sequence of bases as the complementary strand that was unzipped from it, thus making another copy of the previous complementary strand. So your model should have A-T and G-C links only between the strands.

Sure, it makes perfect sense. One wants maximum resonance from the body of the instrument. I would presume the use of drying oils, such as linseed oil, would help repel the moisture from sweat. Which reminds me of that joke in the Molesworth books about the boy not paying attention in a biology class about hibernation: Master: "Molesworh, what are you doing? Pay attention. Now, what does a bat do in winter? Molesworth: "Er....er.......It splits if you don't oil it Sir."

On the contrary, the covid vaccines have saved millions of lives. I have no doubt that air pollution worsens respiratory conditions and will make the symptoms of respiratory diseases worse, or even reduce resistance to infection. However it is mad to suggest that improving air quality is any kind of substitute for vaccines. That really is tinfoil hat territory.

If you want it for musical instruments I think you maybe ought to consider contacting that Greek outfit and asking. They are in the conservation business, it seems, so pretty close to your sort of application. But I take your point about sweat when holding an instrument, such as a violin, while performing. You certainly need something that is not weakened or dissolved by sweat. That is a more demanding application than a picture or piece of furniture, certainly. From looking just now it seems most violin varnishes are traditional, involving things like colophony and linseed oil. There is a lot of stuff about the importance of the varnish not being too rigid or it reduces the sound of the instrument, and issues like that. Well out of my league anyway - I don't play an instrument, only sing.

That fits, certainly. I suspect this product is the resin already fully polymerised, i.e. the curing step was done during manufacture. But let's see if the OP comes back and comments.

I would not characterise it as hubris but I am afraid I do think we are witnessing the end of US dominance of geopolitics, as a result of the possibly terminal dysfunction of its politics. One sees every day authoritarians, in Russia, China and even now Israel, becoming ever bolder, as they see the US weaken. The EU is finding itself suddenly exposed by its tacit and complacent reliance on the US to uphold the rules-based order that has largely held sway since the end of the war. The Chinese are gearing up to retake Taiwan and appropriate the South China Sea. Putin knows if he can hold on for a Trump presidency, he will be assured of success in Ukraine and can turn his sights towards the Baltic States and the Kaliningrad exclave. Israel has embarked on a Final Solution to the Gaza problem, via blatant ethnic cleansing and what looks increasingly like genocide, while the US is impotent to stop it. There is every sign that the US Republican party has withdrawn support for the democratic system, taking a large chunk of the electorate along with them, and instead embraced a loathsome personality cult. The USA will be lucky if its judicial system, its free media and its term limits on presidents survive. The country will be consumed with its own internal problems for the next few years at least. Xi, Putin and others will be rubbing their hands at the prospect. So much for "making America great again".

This is not my area of expertise either, but looking on line, it seems to be an already cured resin, for dissolving in a solvent as a varnish, or as a component in paint formulations etc. I thought this site was interesting: https://www.insituconservation.com/en/products/synthetic_resins/laropal_A81. They seem to recommend it as a varnish for conservation of paintings. I can't imagine they would want to add acid curing agents for such purposes. So my guess would be you just dissolve it in a suitable polar organic solvent, apply it and let the solvent evaporate. But that site, in Greece, has a contact page so you might consider asking them if you need a curing agent or whether you just dissolve it and if so what solvent they recommend.