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Everything posted by greg1917

  1. "Ultrasound can produce temperatures as high as those on the surface of the Sun and pressures as great as those at the bottom of the ocean. In some cases, it can also increase chemical reactivities by nearly a millionfold" http://www.scs.uiuc.edu/suslick/britannica.html
  2. greg1917


    Scientists have not discovered 'chi' as far as I know. Thats a book Ive been meaning to read for a while, and by the sounds of it you should definitely read it. There's a reason many forms of mysticism and vague, wooly spirituality are shunned by most educated people. Its because they're utterly bunk and simply hold no logical ground.
  3. greg1917


    Got to admit that the post that started this thread is one of the most hilarious non-sensical paragraphs Ive ever read. Personally I thought waching Johhny Depp in throws of an intense ether high in Fear and Loathing was amusing enough but this is ether abuse on a higher level
  4. In the exampke you use, hydrogen and chlorine would be far easier to separate if they were cooled to liquid. Chlorine boils at a not too chilly -34.6 degrees C, so could be easily separated from a mixture with hydrogen in this way.Hydrogen boils at something like 20K (or -253 C) so would safely remain in gaseous form throughout the separation. Dry ice should do it.
  5. greg1917


    There isnt really much of a discussion - the book is flat out wrong. An atom with 1 proton and 1 neutron is a hydrogen isotope, deuterium. Helium usually contains 2 protons and 2 neutrons - this isotope constitutes more than 99.99% of helium found on Earth, with the remaining small amount mainly a lighter isotope with only one neutron ( http://en.wikipedia.org/wiki/Helium-3 ).
  6. http://www.madsci.org/posts/archives/jun2000/962225341.Bc.q.html Try the response to this question.
  7. Apologies that took so long for me to reply, i didnt realise Terminator 3 was on channel 5
  8. the reason the phenyl hydrogens are displayed as two peaks has nothing to do with the NH or OH protons whose proximity would only affect the splitting pattern, not the peak integral value. Look at the four hydrogen atoms coming off the ring. If you draw an imaginary line down the ring, going from the OH group to the NH group, you'll see the ring is symmetrical. Ive drawn a (crude) picture to show this: protons A and C are equivalent, as are protons B and D. Thus one of the peaks in the NMR spectrum will correspond to protons A and C, the other peak to protons B and D, both with integral intensity 2 (two protons). This is quite common in para-substituted phenol rings.
  9. Not sure i understand your question about the proton NMR, but having had a quick glimpse at the structure of paracetamol, it should have 5 distinct peaks. Forgive me if this is too basic for you. There are 5 separate proton environments in the structure - the methyl group as you point out, the OH proton, the NH proton and then the 4 protons on the the phenol ring. These last 4 protons will only give 2 peaks. The methyl group should be a large singlet because the nearest proton is the NH proton, and is unlikely to have a splitting effect. The height of the peak is unimportant - its the peak integral you're after, which should be 3, 1, 1, 2 and 2, not in that order. The OH proton peak should (i think) be a triplet as its close to two other hydrogens, and the two phenyl peaks should be 2 multiplets, possibly doublets of doublets. Although if your NMR spectrum is low resolution the splitting patterns may not appear anyway. The coupling constants would allow you to further confirm the structure.
  10. greg1917


    For the benefit of those too lazy to check the other thread with this problem: The green and red triangles are not actually similar. The gradients of their hypotenuses are different - 3/8 and 2/5. Thus neither of the two complete triangles actually has a straight hypotenuse. The one with the filled square has an inward bulge, and the one with the missing square has an outward bulge.
  11. I did focus on it. "So relativity is wrong and they just confuse or ignore you" A ridiculous statement which is in keeping with the quality of the example you cite. Relativity can be observed in any number of situations, none of which you have even drawn reference to, let alone tried to disprove. The thread title of 'relativity is wrong' deserves a thread move to pseudoscience but thats for the Physics moderator to decide (hint hint).
  12. "I'm tired of all these discussions.. " Were tired of people trying to disporve things like relativity and evolution with internet rubbish but you dont see us complaining.
  13. Seeing as everything you've said is conjecture founded on absolutely nothing theres very little anyone can say. The thing is, seeing as theres absolutely no evidence pointing anywhere in terms of what you're suggesting. the only answer anyone can give is maybe.
  14. Seeing as its fake it isnt really an issue. But no, its not ethical, its quite sick in fact.
  15. Criminal investigation constitutes just a part of forensic science. Quincy and CSI are absolutely nothing like real life so ignore any goings on in those programs. Forensics is a very diverse field of science, with chemistry physics and biology all playing a part. See these lecture notes for more: http://ch-www.st-andrews.ac.uk/teaching/lectures/1002/f/
  16. Precisely what have you contributed so far? If you check the post count you might find sayonara has posted about 82 times what you have and in most cases in greater detail. id tell you to read over the thread but it would be wasted advice. Second, stop calling him kid, or young lad. He's more knowledgeable than you are. Just because you heard about cognitive-behavioural therapy from a professor doesnt mean you're qualified to recommend it.
  17. Aside from the magic number rule, there is another principle that applies to radioisotopes. Isotopes with an odd number of protons are likely to be more unstable than those with an even number. Isotopes with an odd number of neutrons are more likely to be unstable than those with an even number. Thus isotopes (like Pb208) with an even number of both protons and neutrons are likely to be very stable. Note Ive said 'likely' in all those statements - there are exceptions to each.
  18. As you'll now, certain numbers of electrons make an atom quite unreactive. 2, 10, 18, 32 There also appears to be 'magic numbers' of stable protons and neutrons. 82 happens to be one of the numbers in this series - lead is element number 82. the reasons behind nuclear stability are pretty advanced. http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch23/natural.html Same but reworded: http://ottawa.rasc.ca/observers/an9506p3.html A pretty big page on all sorts of nucleosynthesis and nuclear stuff. peruse at your leisure. http://www.astro.queensu.ca/~hanes/p014/Notes/Topic_058.html
  19. Im still waiting for an explanation how anything can be >100% efficient
  20. Perpetual motion in the sense Ithaxa is talking about is impossible - inventors having been dreaming up perpetual engines for huddnreds of years, ranging from simple contraptions using the falling motion of balls to massive engines which pump water to high tanks and use it to power turnines. Perpetual motion in the sense of say, electrons flowing through a superconducting loop is (off the top of my head) the closest thing to perpetual motion in nature.
  21. You can do lots of things to make it NEARER perpetual motion. Evacuating the surrounding air will decrease the amount of energy escaping from the system, but not eliminate it. It might continue going for a long time but will eventually stop. And anyway the whole point of a perpetual motion machine is being able to extract energy from the system to power something - the minute you extract any energy from this system, it slows down/stops. Despite Ithaxa's best efforts he's never going to build a perpetual motion machine. He can add more magnets, conveyor belts and more string than you can shake a stick at, but energy will be lost as friction and the magnets will simply not be able to keep the balls travelling as fast as is needed.
  22. Although its an interesting idea, I dont really see it going anywhere because reactions involving silicon aren't at all similar to the massive range of reactions involving carbon compounds. I dont see how you could have a protein or nucleic acid substitue for silicon, or one of the many organic building blocks like isoprene or ribose (for that matter a carbohydrate substitute as well). Some sort of range of membrane systems is absolutely fundemental and life absolutely will not exist without it; proteins or something similar are needed here. I think youll have to employ quite a bit of artistic licence...
  23. My last exam is on May 26th. After that Im free for the Summer - hopefully be going to the Isle of White festival.
  24. Bismuth is the last element a star can produce via the s-process of element nucleosynthesis. Beyond this, supernovae are needed to make elements past z=83. This means the uranium deposits on earth must have been come from by a supernova explosion somewhere in the galaxy that threw material over to our side of the cosmos. Iron is the last element that is produced via 'regular' element fusion. Iron inhabits the peak of the binding energy per nucleon vs mass number graph, so will not fuse as doing so would actually absorb heat from the star core. Evidence can be seen from the spectrum of our sun, and other stars.
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