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John Cuthber

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Everything posted by John Cuthber

  1. At least "actually" isn't actually wrong.
  2. Why is that happening? Oh, I forgot, it's government policy. https://www.washingtonpost.com/blogs/answer-sheet/post/texas-gop-rejects-critical-thinking-skills-really/2012/07/08/gJQAHNpFXW_blog.html
  3. It's interesting that, as these are phased out, the same idea is being used to do a different job (on a smaller scale) https://en.wikipedia.org/wiki/Gas_holder
  4. Without collaboration is is rock solid certain that civilisation and technology would not develop. Competition is more or less the opposite of cooperation. The usual way to defeat bullies is not that bollocks about "standing up to them". (That just gets you beaten up) The solution is ganging up on the bullies. People who are given to cooperation are, therefore better placed to defeat bullies. So, for bullies to succeed, one thing they will seek to do is to reduce cooperation among those who they want to exert power over. A way of doing that is to set them in competition with eachother. So, for example, if you tell the low paid workers that their enemy isn't the billionaire but the immigrant... It's not an absolute thing- the best you can say is that encouraging collaboration drives down bullying and drives down competition.
  5. That seems unlikely given that breweries have been (carefully) using the same strains of yeasts for decades or more. However, if you needed a fresh supply, there's no need to trouble the animals, just wait a while with a bucket. https://www.jstor.org/stable/25031792?seq=1
  6. Except that it means something different. Specifically, it's an insult to the Hawaiian language to say that it's phonemes are "least", rather than that they don't use many.
  7. None of that box will reflect UV well. Did you understand this bit of what I said?
  8. Given the yellowish colour of that card, I would say it will absorb UV . If it was white card (or maybe blue) I'd expect it to reflect it. The problem is that you can't see UV so it's hard to tell
  9. Does this help? https://www.sigmaaldrich.com/catalog/product/aldrich/r350893?lang=en&region=GB Why do you want an IUPAC name for it?
  10. It's a radioactive atom. It will decay; once. There will be a brief flash of light. But there won't be any indication of the path the molecule was following when that flash happened.
  11. Fewest. (Well, it's a discussion about words..)
  12. If you just want to count words should you bother with all the variations? If I know the verb "walk", I can deduce some of the variations "walks" "walked" "walker" etc I'd need to learn the use of "walk" as a noun, separately. But from that, I can deduce a plural- "walks" If I was counting the words in a language with a view to choosing one to learn, I might not need to count the words like "wugs" which I'll never need to remember because I can "create" them when needed. But do I count walk(v) separately from walk(n)? Perhaps I should. To the extent that there's a rule in English for making verbs into nouns, I should go to a walking, in the same way that I go to a meeting. It looks very much like the answer to the question "Which language has most words" is "it depends" BTW, since the title of the thread lacks a question mark, it is a statement. So what's "which language"?
  13. Yep. Just make sure it's a randomly chosen spectroscopist.
  14. Mainly wrong. For a start https://en.wikipedia.org/wiki/Infrared_spectroscopy#Liquid_samples Also, re" We are only interested in motion that can lead to translation (ie evaporation) and that is the first one on my list." No If you look at a simple molecule like water you can calculate (quite easily) the number of possible vibrational modes it has. Each atom can move in any of 3 directions, (x,y and z). There are 3 atoms in a water molecule. So there are 3X3= 9 possible ways in which the atoms can move. But three of those correspond to rotations while (and here's the important bit) three of them correspond to translations. So there can be no more than 3 vibrational modes for water- it absorbs (fundamentally) at just 3 wavelengths. https://en.wikipedia.org/wiki/Infrared_spectroscopy#Number_of_vibrational_modes So the movements that you are interested in- the translations- are definitely not vibrations. (Just in case you are wondering, for linear molecules where rotating about the axis of the molecule isn't defined, there is one less rotational motion and thus 3n-5 possible vibrations.) Actually, what you want is a variable restoring force- if it varies linearly with distance you get a sinusoidal vibration. Molecules have bonds. Those bonds behave (classically) as if they're springs.
  15. "Do molecules below the surface of the liquid evaporate?|" Usually, but... https://en.wikipedia.org/wiki/Cavitation
  16. Vole = rearranged love letters. Yes and no...
  17. All of them; but by proxy.
  18. I'm not actually sure about that. Would it need to be stronger than a stone arch? If it is x times thicker it weighs x times more, but there's x times more stuff to hold it up.
  19. Is now. DD reactors exist. I'm thinking of making myself one as a toy. https://en.wikipedia.org/wiki/Fusor
  20. To be fair, while "zero" is the right answer, it's not obvious. So, here's the proof. https://en.wikipedia.org/wiki/Shell_theorem#Inside_a_shell And now that the only scientific question posed has been answered, I don't see any reason for this thread to remain open.
  21. The OP starts with "ok i think i may have phrased it wrong " and that's a good honest statement to make. But it does make discussions about exactly what he meant, a bit tricky. It's true that he didn't say anything about explosives. But If I ask "what's the heaviest mammal?" I'm going to get answers that relate to whales. There's some clever stuff with diamond anvil presses that get to about 10 million bar. But that's not really chemical. I think explosions get to nearly a tenth of that . There are some chemical reactions that take place in the range between those two. Metallic oxygen forms at about a megabar. So the decomposition of metallic oxygen would generate about a megabar. Does that count?
  22. Do you mean a rugby ball? It depends on the azide some aren't explosive, others are. ANd sometimes people accidentally convert the first group into the second. Nitrogen is good, mainly because the NN bond in N2 is strong. Making nitrogen gas generally releases a lot of energy and a gas. Those are both good for high pressure generation.
  23. This may be of interest. https://en.wikipedia.org/wiki/Trauzl_lead_block_test
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