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jdurg

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Everything posted by jdurg

  1. Just because something doesn't detonate doesn't mean it's neccesarily stable. If I recall properly, NaOCl will decompose into sodium chloride and oxygen gas relatively passively.
  2. Well Chernobyl was an accident waiting to happen. It was a poorly designed system and run by people who weren't given all the information they needed to run it safely. I mean, they purposely turned off ALL safety mechanism to run the fatal test which led to the plant completely failing. Then, the surrounding people weren't informed of what was going on and the emergency personnel weren't properly informed either. (I mean, they were pouring water onto the liquid sodium/graphite fires!). At Three Mile Island, a mechanical failure occured yet the safety systems put in place contained the 'incident'. You hear a lot of stories saying that x-amount of radiation escaped, but I find that laughable because how can radiation escape if there is no structural breach of the reactor? Yes there was a partial core meltdown, but the containment system kept the core intact. In reality, TMI was a great example of how the safety and backup systems in a Nuke plant can prevent a major accident.
  3. American and British Nuke plants are remakably well built. However, in 'poorer' countries which are just starting to get nuclear power plants, the structures aren't exactly 'plane worthy' and it's in those places that you have a lot to be concerned with.
  4. Another argument to be aware of is the 'nuclear power plants don't consume fossil fuels'. In reality, they do consume quite a bit. The act of processing the raw ore into a useable fuel requires a great deal of fossil fuel consumption. The plant doesn't directly use fossil fuels, but it indirectly uses a good amount of it.
  5. With the insanely high temperature present in and around the black hole, wouldn't it be logical to assume that the nuclei are free of electrons? (We all know that in the sun there are no electrons. It's all just a giant ball of plasma).
  6. Everything looks fine to me in questions 1-4. In question number five, in the equation you're solving for x which is the H+ concentration. The A- concentration is exactly the same, but you forgot to solve for the HA concentration. HA should be 0.100 - 0.0013 = 0.0987 M. Otherwise it looks good to me.
  7. No. It is not possible.
  8. Acetylene is FAR from poisonous.
  9. The phrase 'When in Rome' just took on a whole new 'not so nice' meaning.
  10. You can take your sulfur and add some mercury to it. The sulfur will soak up the mercury making a dark 'sludge'. In reality, sulfur is used to clean up small mercury spills because it soaks the stuff up like a sponge, and once soaked up it doesn't want to give it back. I have my mercury samples surrounded by sulfur in the rare chance that the container breaks.
  11. If you go by the literal definition, then no, ammonium hydroxide doesn't exist. When ammonia gas is placed into water, you get NH4+ ions and OH- ions along with aqueous NH3. However, if you evaporate the water again you don't get NH4OH left over. The NH3 leaves solution and you just get water. Inside the water, you don't have the NH4+ and OH- ions forming dissolved NH4OH as a stable species. Instead the NH4+ will donate a proton to the OH- ions giving you water and ammonia gas again. So by saying that NH4OH doesn't exist isn't saying that adding ammonia to water doesn't make a basic solution. It's just saying that when you add ammonia to water, you don't get NH4+ ions, OH- ions, and the NH4OH species floating around. The proper equation would be: NH3 + H2O <=> NH4+ + OH-
  12. That all depends on your definition of a 'base'. Just like most things in chemistry, there are multiple definitions that need to be kept in mind when saying something. Saying something is a 'base' is like saying something is 'reactive'. You need to specify your definitions when making the classification.
  13. Just remember that Barium is very toxic in the form of a soluble salt. Make sure you don't contaminate ANYTHING with the barium otherwise you can get yourself and others very, very sick.
  14. Eventually it would completely decay. It's just that when you get to such small numbers of atoms, you can't be really too sure when it will decay since radioactive decay is a spontaneous event. That means that it will happen whenever and wherever. With large, measureable quantities of atoms, you can use the half-life to determine how much is left due to the incredibly large sample size. When you start getting down to the level where you can physically count the atoms, you really can't go by the half-life since the sample size is so completely small. Thinks of it this way; if you flip a coin 80-trillion times, the probability that heads is flipped will be about 50%. If you only flip a coin 4 times, however, there's a good chance that the probability of heads will work out to be 3/4 or possibly even 4/4. So if you have 80-trillion-trillion-trillion Uranium atoms, the chances of half of them decaying over the next 4.5 billion years is near 100%. If you have 80 Uranium atoms, the chances of only half of them decaying over the next 4.5 billion years isn't exactly 100%. You may only get five atoms decaying, or you may get 78 atoms decaying, or you may have all of the atoms decaying by that point.
  15. That's not really how half-life works. The half-life is a measurement of the 'average' decay rate of a sample. It's really just a probability. It says that in 15 minutes, the probability of half the sample decaying is close to 100%. As you get down to smaller and smaller numbers of atoms, you don't have a large enough sample size for this 'probability calculation' to really mean anything.
  16. Okay you've got a good background on what potential energy is. Potential energy is the energy something can 'potentially' use if it needs to. When you hold a lead brick above the ground, the brick has a bunch of 'potential energy' because it can potentially release it if it falls down to the ground. Electrons and atoms are the same way. The electrons in one atom have an attraction to the nucleus of that atom, or of another atom. Remember that the nucleus is full of protons which are positively charged, and electrons are negatively charged. Because of this attraction, the electrons need to have a certain amount of energy to avoid being swallowed up by the protons. They have this energy in the form of kinetic energy (I.E. energy of motion). The electrons are whipping around the nucleus at fast speeds so that they don't get sucked into the nucleus. The overall energy that the electron has is quantized; that means that it is a set amount of energy. So the electron has the kinetic energy of it moving around the nucleus, but it also has the potential energy due to its distance from the nucleus. This potential energy is the amount of energy it could give up by falling closer to the nucleus. So if you're close to the nucleus, you have a lot of kinetic energy but a little bit of potential energy. (It's like having a brick only a few inches above the ground. Not much potential energy there). Electrons all move around the nucleus at about the same speed, but those that are further away have more energy because they have a higher potential energy. (Since they are further from the nucleus. It's like a brick that's two feet above the ground compared to one that's two inches above the ground). So what happens when two atoms combine into a molecule? Well when they are lone atoms, their electrons have a set amount of energy between the kinetic energy and potential energy each electron has. The electrons that are involved in reactions are the outer electrons of the atoms, so they have an elevated potential energy. As an analogy, let's say that Atom A is a five story building and Atom B is a 6 story building. There's a lead brick on the top floor of each building which has a set amount of potential energy in it. When the two atoms combine, it's like they combine into one bigger building that is only 3 stories tall. As a result, those lead bricks have to drop a few stories in order to remain on the top floor. They thus lose some potential energy and it goes out as the kinetic energy of them falling. The same thing happens to electrons involved in a chemical reaction. In the individual atoms, they have a certain amount of potential energy due to their distance from the nucleus. When they combine, they wind up at a different distance from the nucleus. If they are to stay at this distance, they have to give up some of their energy. (Since when you're closer to the nucleus you have less potential energy). This difference in energy is what is given off as heat and/or light in an exothermic reaction. In an endothermic reaction, it's as if those two building combined and made an even taller building. Now, in order to remain on the top floor, the lead bricks have to take in some energy in order to move upwards. As a result, they will absorb energy from the surroundings. This is seen by endothermic reactions as the temperature drops. Does this kind of make more sense?
  17. Let's not forget that we don't use carbon dating to get the exact, to the minute, age of something. It's there for an estimate to within a few hundred years. If you believe strongly in creationism you will NEVER believe ANY of the scientific evidence no matter how conclusive it is. Now back on topic here. I believe the original poster was asking about how do we know that the radiation we're measuring is from Carbon-14? That's pretty simple. Each isotope has its own distinct energy when it is given off. It's a fingerprint, so to speak. When a carbon-14 atom decays it gives off rays of energy of a very specific magnitude. By calibrating the instruments to only pick up that magnitude of energy wave, you can isolate the decays being measured to that of C-14. Also, the decay rate of an isotope IS steady. I have yet to find any research being done that shows a fluctuating decay rate of an isotope to an extent that it would severely alter the half-life of said isotope. Yes you can get isotopes to decay quicker than normal, but that's only through forced fission of the isotopes. With light atoms such as C-14, you're not going to get that to happen. So the decay rate is constant and if it's an assumption, then it's just as much of an assumption as saying that if you drop a brick it will fall to the ground.
  18. Exactly. Or they'd throw in some other 'glow in the dark' stuff that required exposure to sunlight in order to glow.
  19. With the radium paint, ZnS existed in there anyway. Radium salts on their own will not glow unless you have so much of it that it will kill you. The hands were painted with the RaCl2/ZnS mixture which led to the glow as the emission of radiation from the radium 'excited' the ZnS. Many of the watch hands quit glowing not because the Ra had decayed, but because the ZnS failed to function.
  20. H2 and O2 can also be kept as a mixture and be relatively stable. If you have pure H2 and pure Cl2 mixed together, UV light (a.k.a. sunlight) will overcome the activation energy barrier and cause it to violently start reacting. (It's actually kind of neat to see).
  21. So I contradicted myself by explicitly stating that there are exceptions? Wow. I guess I better not say anything anymore. If yo look at Title 21 CFR 1310.03, you'll find the following quote; "However, a non-regulated person who acquires listed chemicals for internal consumption or "end use" and becomes a regulated person by virtue of infrequent or rare distribution of a listed chemical from inventory, shall not be required to maintain receipt records of listed chemicals under this section. " That statement right there says that if you infrequently use the substance and have no plans on further distribution, you have no reason to be reported or be worried about arrest. Therefore, unless you're doing something illegal with those chemicals you have NOTHING to worry about. If you read the DEA's website, you'll also see that the DEA is concerned with watching the manufacturers and distributors of these chemicals, not the end-user itself. We also find on the DEA's website the following quote; "Advise all distributors of these List I chemicals that it is unlawful for any person knowingly or intentionally to manufacture, distribute, export, or import any equipment, chemical, product, or material which may be used to manufacture a controlled substance or listed chemical, knowing, intending, or having reasonable cause to believe that it will be used to manufacture a controlled substance or listed chemical in violation of the Controlled Substance Act…21 U.S.C. 843(a)(7). Persons who violate 21 U.S.C. 843(a)(7) may be subject to criminal or civil penalties." That quote, simply put, says 'if you purchase any of the equipment or chemicals with the intent to make illegal substances out of it, then it's illegal'. Well DUH! If you have the stuff lying around and there's no intent or goal of making a controlled substance with it, then you've done NOTHING illegal and you will NOT be arrested. Why should you worry about whether or not someone has your name on record if YOU AREN'T DOING ANYTHING ILLEGAL? I said earlier that the U.S. government won't bother spending the time to watch over Joe Shmoe and his one purchase of red phosphorus. I still stand by that after reading through the DEA's website. The only thing the DEA mandates is that the SELLERs keep track of their sales. The DEA just wants the purchasers databased for evidence purposes. Let's say Joe Shmoe is buying red phosphorus and ephedrine from a whole bunch of different suppliers and is for some reason arrested. At this point the DEA can look and see that he's been arrested for methamphetamine possession and has bought a ton of chemicals due to the databasing of all these transactions. The DEA doesn't spend every day picking out people to go and arrest. They just use this 'evidence' as a massive source of leverage when litigating these drug users. If you are someone who is a drug manufacturer or user, then you deserve to be locked up and thrown in jail. If anybody comes to this forum looking to buy chemicals for illegal purposes and is arrested, then GOOD!
  22. Unaltered ethanol cannot be purchased without a license simply because of the fact that it is dirt cheap and you can drink it. Because of this, the government has mandated that all 'tax-free' ethanol MUST be denatured by the addition of some difficult to remove and unpleasant chemicals. These denaturants typically don't alter the chemistry of whatever the ethanol was being used for, but they make humans horribly ill if they ingest them. If you want/need perfectly unaltered ethanol, you must have a license for it and basically pay an alcohol tax on it. For diethylamide (Or diethylamine, I can't recall the exact name), it is illegal to posess because the only use for the compound is in the manufacture of LSD. There have been no other uses for it that can't be accomplished via other chemicals. For the making of LSD, however, that chemical MUST be used. Because of this selectivity, the government has decided that there is no need for any person who's not making LSD to posess the chemical.
  23. Okay budullewraagh, I know you're trying to keep people aware of things, but please don't make an accusing post like that without 100% proof of what you're saying. Doing something like that in an open forum on the internet may be construed as libel and could get YOU into some serious litigation issues. I myself have never purchased any chemicals from them for the many points already made in this thread. They are a bit pricey and they really haven't carried anything I want. I have a better time getting chemicals from E-Bay and Unitednuclear. As for possession of those chemicals being illegal, that is far from the case. You can possess ANY chemical in your home that you want and the law enforcement will have no bounds to arrest you. Now if you try to make an explosive or a drug or toxin of some kind, THEN the possession of those chemicals can be enough to get you arrested. Someone going and buying a pound of red phosphorus will NOT, and I repeat, WILL NOT get you watched by the FBI/DEA/SS/etc. etc. It's simply not worth their time. The amount of time and money it takes to monitor people buying the chemicals is simply not feasible. One other thing to remember is that if you're not doing anything illegal, then who cares if the police know about what you have? I've had the post office ask me many things before when boxes would arrive with Hazmat labels and all this other stuff on it. I just told them that I have chemistry as a hobby and told them everything I was doing. I got some strange looks but never had an officer stop by my house or ever have any mail withheld on me. Christ, the U.S. Government knows that i've been going arond purchasing Uranium metal and they haven't done anything but send me an e-mail politely answering all my questions about the legal possession and storage of it. Posessing chemicals isn't like possessing drugs. With drugs, the amount of the stuff you possess can give the government enough proof that you're a 'seller'. Don't forget that it's ILLEGAL to posess ANY amount of a controlled substance. With chemicals, just because you have two pounds of a substance doesn't mean you're a bomb maker or a drug maker or whatnot. The only way it can mean that you are a bomb/drug maker is if you ALSO have some of the bomb/drug in your posession. If there's a chemical that the government doesn't want you to have, they'll simply make it illegal to sell it. Unaltered ethanol is one such chemical, as is diethyl amine (or amide, I can't recall the exact name). The less they want you to have it, the more difficult it is to get it.
  24. Logically it would make sense, however. Since bromine is between chlorine and iodine, it's stronger than iodine but weaker than chlorine. The combination of iodine and chlorine results in a compound with a high enough molecular mass to be a liquid, while it's slightly weaker than chlorine but stronger than iodine.
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