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John Cuthber

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Everything posted by John Cuthber

  1. OK, that explains why he has to worry about it, what about the rest of us.
  2. I think the only real answer is to run away, fast.
  3. To understand molarity you need to know what a mole is (and I don't mean a small burrowing mammal). This might help http://en.wikipedia.org/wiki/Molarity#Molarity
  4. It seems to me that they really should have thought about how they were going to pull out before they went in.
  5. "4. Yes, at room temperature there is only really 3 pure metals, iron, cobalt and nickle" Er, there's certainly a 4th; gadolinium is magnetic too. I did once hear that one of the crystal modifications of plutonium is too, but I don't feel like checking that one so I don't know if there's a 5th. BTW, why do so many people spell nickel wrongly? "I should have said above that diamagnetic materials will also stick to magnets." No you shouldn't. Diamagnetic materials are repelled by magnets. "It's a diamagnet (a very very strong one) which means in the presence of an external magnetic field it will become magnetised (and therefor magnets can stick to it)." No, it doesn't mean that at all. While bismuth and pyrolytic graphite are strongly diamagnetic as diamagnetics go, the effect is still weak compared to the effect of a magnet on a steel nail.. Most compounds are diamagnetic including water. Since yiou are mainly water you could be held up by a sufficiently stong magnetic field gradient.
  6. If enough people do that you get a negative rate of inflation (and broke).
  7. I want to know where he buys his radioactive nitrogen from and how he gets it delivered before it decays?
  8. If taking people and imprisoning them for no clear reason is an act of war then, thanks to Guantanamo bay , Brittain and Australia (among others) should declare war on the USA. Diplomacy seems like a better bet. I suspect the Iranian sabre rattling is more to do with propaganda aimed at the Iranian people. I feel sorry for those taken prisoner and for their fammilies but I really don't see a military solution to this.
  9. Snail, you said "Ounces and fluid ounces are different". In a very real sense; one is weight and the other is volume. But (from the OED) here are the conversion factors. liquid measure One pint=20 fluid ounces = 0.568 Litres Weight (avoirdupois) 1 pound =16 ounces 1 ounce = 16 drams = 28.35 grams To the extrent that 568/20 ie 28.4 is not the same as 28.35 (and, let's face it; that's just a rounding error) it is true to say that an ounce is not the same as a fluid ounce. A fluid ounce of water weighs an ounce, and an English pint is 20 ounces or 568 ml. I'd still like to know how strong typical beer is in the US.
  10. Don't forget that you don't start from zero ppm CO2.
  11. If exactly half the total nitrogen is ammoniacal nitrogen then it's probably ammonium nitrate, for pure ammonium nitrate it would be 35% total nitrogen. Chemhero, Do you actually think "NH3-N" is a compuond?
  12. Lime kilns have been practical since at least Roman times. Not easy to set up in the kitchen.
  13. I still don't understand how this is a war. On whom was it declared? Which are the neutral countries? Probably most important are 2 related matters How will you know when it ends? Who will sign the armistice? Until we have answers to those, all this talk of "all's fair in love and war" is irrelevant.
  14. I understand that many people in the Western world have pesticide levels (particularly DDT) that are higher than those permitted in food. People, like most animals, have quite high protein levels and low carbohydrate levels. While it's possible to get by on that for a while it's far from ideal because we would have to produce energy by protein metabolism; breaking them down to produce the energy required to make carbohydrates (the brain can only run on glucose). A better aproximation to "what we really out to live on" might be milk, but even that will be far from ideal. An entirely carnivorous diet would also contain lots of iron- we would need to shed most of this; there are studies that link high iron levels to heart disease. I'm sure we are short on B group vitamins too. If you were looking for the best way to transmit parasites, eating raw human flesh would be a pretty good start. One final point in favour of eating people. Imagine I take a muscle biopsy from my own thigh and culture it up. Is this the only morally acceptable way to get a steak? The animal from which the meat is derived explicitly consented to being used in this way; cattle don't.
  15. Can I just check on something? Bush is saying he will veto a decision, made by the representatives of the US population, to withdraw the troops who are meant to be there to bring democracy.
  16. My word! Do you lot really not know that a pint is 20 ounces (568ml)? For the record a gallon is 8 pints or 10 pounds of water (about 4.54 Litres). The stone (14Lbs) makes perfect sense- it's half a quarter. A quarter is 1/4 of a hundredweight and 20 hundredweight make a ton (2240 pounds). BTW, what's the typical strength of American beer (I realise there will be a huge range; whats the mode?)
  17. Money is a medium of exchange. It can stand for hours worked but, since my hourly rate of pay is more than some peoples and less than others it can't be that simple. I'm not much good with animals but I like eating meat. The farmer doesn't have much tallent as a chemist but, ocasionally he wants the benefit of knowing chemistry. If those were the only two jobs in the world it would be fairly simple for us to simply get together and agree an exchange rate; they feed me and I check the concentration of stuff in their sheepdip and the vitamin levels in the feed (or whatever). Once you have many jobs going on- a potter or baker would probably have been a fairly early profession (and we needn't worry what profession was first) things get complicated. It makes it much easier to have an accepted mechanism for agreeing how to get the chemistry, farming, pottery and bakery done by those who have talents for those jobs. There may be other ways to achieve this but money seems to work quite well.
  18. If you are planning to replace it you might want to look at heat pumps.
  19. Respect can go any way it likes. If your country, even in a single instance, decides to suspend the presumption of innocence and the right to a fair trial then anyone else from any other country is able to judge your country on the basis of that decision. GWB and co decided to go that way and at that point I decided that they ought not to be in government. I doubt I'm the only one. For what it's worth, current opinion poles here are running about 2:1 that we should not have invaded Iraq. I'm not certain, but I think more people have been killed by terrorist and related acts since the "War on terror" started than were being killed before; perhaps having it stalled by the lawyers might be an improvement. You say "There is no question that he is an enemy combatant." I say no, he's just a terrorist and there's no need to make up new names for it. More importantly of course is the fact that, while there is clear evidence to arrest him and bring him to trial (and there was, as you say, before anyone tortured anyone, that video footage) that's a poor argument for detaining all the others without trial. "No country has yet come to grips with how age old precedents should be applied in an asymetrical war where the combatant would take out one of our cities given a chance." Which side is which here? As far as I'm aware, the ony comabatant involved who has the miliitary strength to take out a city is the USA. What the other side would do if it could isn't important since they simply don't have the power.
  20. Just a thought, quite a lot of this topic seems to debate the effect of temperature on steel and says that jet fuel doesn't burn hotter than about 1000C. Here's a quote from the Wiki article about jet engines. "Cooling systems All jet engines require high temperature gas for good efficiency, typically achieved by combusting hydrocarbon or hydrogen fuel. Combustion temperatures can be as high as 3500K (5000F), above the melting point of most materials. Cooling systems are employed to keep the temperature of the solid parts below the failure temperature." You can melt copper (at 1083C) in a candle flame so the idea that a straightforward saturated hydrocarbon fuel like jet fuel won't get that hot is strange. Blacksmithing is done with red hot steel. The flames in the WTC are clearly glowing at least that hot.
  21. I'm not sure but I think R-Q = the set of irrational numbers.
  22. Dismissing "Quote: You've thrown out due process. You've allowed torture. You've destroyed the presumption of innocence. You've alowed secret prison camps. Exactly how is your legal system now any different from that of Stalinist Russia? " As "Hyperbole." doen't actually answer the question. Why should I (living in England) have any respect for a government that does those things? Similarly deriding the idea that some Austrailians might be waiting for the Gitmo detainees to "confess" under torture to things they simply didn't do as "kind of silly" avoids facing up to the real possibillity that they will do so. That's why civilised countries do not condone torture (except possibly during wartime, and I remind you that this is not a war).
  23. The answer to the original question seems to be yes. http://www.webrankinfo.com/english/seo-news/topic-5417.htm Also, there are 2 things to note about the return radar signal reflected by an object, how big is it and how much is it Doppler shifted. Birds and moths don't travel at the speed of sound so they can be discriminated from planes that do. This is complicated by the use of "chirped" radar pulses.
  24. The temperature is related to the average speed; when it's cold there are a few fast movers which have enough energy to react and a lot of slow ones that don't. When you heat things you get a bigger proportion of the molecules moving fast enough to react so the rate of the reaction increases. If you want to know about the maths you need to find out about Boltzmann distributions .
  25. Actually, to be a bit more specific, silver nitrate reacts with chloride rather than chlorine. Since Cl2 dissociates in water to give chloride it is true to say that silver nitrate will give a ppt with a solution of chlorine. On the other hand, if you wait a while for the chlorine to difuse out of the water (or better yet, bubble air through it) then test with silver nitrate you will still get a ppt. It won't tell you if the chlorine has gone. It would, for example give a really strong positive test with seawater but that has essentially no free chlorine. Measuring free chlorine is a bit more tricky I think there are kits to do this; sold to aquarium owners. If I wanted to dechlorinate water for an aquarium I'd probably just put pondweed of some sort in it and wait for a day or so. The plants might take a bit of a hammering but it would save the fish.
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