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John Cuthber

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Everything posted by John Cuthber

  1. Last time I checked all reactions were reversible; in some cases the equilibrium is very much to one side.
  2. I presume the 1st ammendment is about freedom of religious belief. That's a potentially interesting point. Imagine I want to sell snake oil. presumably the people who buy it have some belief that it works. Is the government right to rule out that belief by prosecuting me for fraud? What if I was genuinely mistaken about the snake oil and I believed it worked?
  3. I wonder if they were trying for this. http://en.wikipedia.org/wiki/Delphinidin
  4. I didn't mention heating it, but I did say it would then need cooling. On the other hand, before you said it needed singlet O2 or O3 someone had already clarified the need for heating etc.
  5. "Have you ever noticed the differing kinds of sweetness across apples? Some are sweet like honey, others are sweet like sugar, others molasses, others with more a "corn-like" grainy sweetness..." Well, I don't like apples so I haven't noticed this, but I can't help wondering why the people who do research on taste haven't spotted this distinction yet. They only seem to have come up with salt, sour, sweet, bitter, and umami.
  6. Textbooks are sometimes wrong. Do you have any evidence for the existence of Cl2O5? There are some other oxides of chlorine and they are not generally easy to work with so it can be hard to tell if you have a new compound or just an impure mixture of the other oxides.
  7. Actually, I think my having done the experiment proved it. Incidentally, thermodynamically speaking, the oxygen in the air should combine with the nitrogen and the oceans to form nitric acid. If anyone finds a good catalyst they might be in real trouble.
  8. Can an omnipotent God set Himself a task He can't acomplish? Does an omniscient God know a question He can't answer. After a while this sort of thing doesn't seem to be going anywhere. There are plenty of impossible things.
  9. Calcium carbide is paerfectly capapble of removing any water from silica gell. Adding the gell would increase the amount of water present (since it's never perfectly dry) and thus increase the wastage of the carbide. It's more important to store it in a sealed container, adding a "drying" agent like silica won't help.
  10. "if it were Singlet Oxygen yes perhaps, or even Ozone, but not O2." Er, not really. The oxidation of ammonia to NOx is the basis of the commercial production of HNO3. As was already mentioned you need a hot catalyst. I have done this reaction using copper oxide as a catalyst- the yield wasn't good, but it worked.
  11. "Ethyl nitrite, prepared from the reaction of ethanol with sodium nitrite and sulfuric acid, was formerly a widely-used diuretic." Sure about that?
  12. If you were as clever as you seem to think then you would have noticed the trick with NaHSO4 and alcohol had already been mentioned, as, of course, has the oxidation of SO2 with H2O2.
  13. This is a reasonable start. http://teaching.shu.ac.uk/hwb/chemistry/tutorials/chrom/gaschrm.htm What valves in particular did you have in mind? The potential problem is that the exact details will depend on the particular GC you have.
  14. IIRC there are speciality HPLC columns that are used for separating sugars which rely on boronic acid groups bonded to the mobile phase. Glycerol definitely forms some sort of complex with boric acid and this might be employed in some way, like the HPLC columns, as a way to extract the glycerol.
  15. Interestingly, so is the reverse process, possibly just as well, elephants may be endangered but we don't need as many of them as we have electrons. If you take account of the idea that some things take time and effort even more things become imposssible. It might be possible to put a man on Mars; but it's impossible to do it this weekend, or cheaply. Since I don't expect to live forever, a whole lot of things are impossible for me. Taking those limitations into account it seems that a vast number of things are impossible. The next question would be are more things possible than impossible? This involves comparing two infinte sets and I'm not sure if that's impossible.
  16. To liquefy hydrogen you need to make it very cold (about 240 below zero). Even at that temperature you need to compress it too (to about 13 atmospheres). To get it liquid at normal pressures you need to cool it another dozen degrees or so to about 253 below . I wonder where you have ever seen liquid hydrogen, it's not easy to see- it is cold enough that the air round it liquefies too, then the air freezes. Liquid hydrogen isn't easy to work with.
  17. "I think that the sulphuric acid might have aluminum sulfate in it, although I'm not sure what that would do..." Among the things it would do is dissolve in sulphuric acid, but not in alcohol.
  18. From time to time I hear about a tragedy where someone has entered a tank or well or some such and been overcome by fumes- his friend has gone in to help and has also been rendered unconsious then died too. Sometimes a third "wannabe hero" dies before someone catches on and gets the help of the fire service or someone who has breathing apparatus. Cleaning up an ether spill is potentially lethal for at least 2 reasons. The fumes can incapacitate you, and the stuff is damn near spontaneously flammable. OK, so there's no bunsen burner. Unless the guy was naked there's a severe risk of static elctricity from clothing causing the last spark he ever needed to worry about. Hermanntrude's solution to the problem was better, but the bit about holding his breath gives the game away. If you need to do that they there's not enough air. If there's not enough air then you shouldn't be there. If this sort of thing happes again leave the area and make sure everyone else does, sound the fire alarm if there is one. Let people who have air tanks and fireproof clothing worry about it. If you have any doubts about this advice, call your local search and resue or fire dept. I'm sure they will explain they would rather turn up to open a window or two than to recover a body.
  19. Midgetwars, if you really think "NOthing is impossible if you think logically everything is possilbe" Perhaps you would like to take up the challenge about the square root of two?
  20. "In what base?" Any integer you like- btw, non integer bases are a bit odd anyway.
  21. According to wiki Ti catches fire at about 610C.
  22. iNow, please find me a rational square root for 2. Let me know what time and resources you need.
  23. I don't see evidence of out ethics declining with time. I'm sure the Romans were better at organising orgies than we are now (No, I can't prove that). There seems to be evidence that people are waiting longer to have sex. Even if it were the case then there's another factor; people are not actually stupid. If the rates of HIV ever got anything like that high, people would start being more careful about their sexual behaviour.
  24. There are problems caused by drug use. There are also problems caused by the illegallity of drug use. We can't prevent the former (any number of attempts in the past have patently failed since the drugs are still used). We can do something about the latter. It's possible that the reduction in damage done to society (however you may chose to measure that) by removing the latter set of problems outweighs any increase in damage done by any increase in the former set of problems.
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