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VendingMenace

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Everything posted by VendingMenace

  1. lol...stupid me. I did mean to say "more" when i wrote "less" instead. I think swansont has cleared up this confusion. Wow, that was dumb (on my part). I guess...though post#11 makes it pretty clear that he was talking about the vibrations of the molecule. Whatever. This discussion has way outlived its usefullness, i think it is clear that vibrations and rotations are usually not of the energy required for the breaking of a chemical bond or the overcomming of a activation energy...at least not anything that anyone has thought of yet. THough, i have been thinking about this and there seems to be a few cases where this might not be the case... 1) If you count the temperature being raised in solution by vibrational and rotational transitions (ie. in a microwave). 2) Perhaps in a very unstable molecule like tetrazine vibrational excitment *might* lead to decomposition. But i really don't know. 3) In redox systems that are undergoing self-exchange of electrons, if the system is strongly coupled enough, then there can be a phenomenon called vibrational coupling, where the electron transfer event can depend strongly on the vibrational modes of the molecule. I think that is it for now. At least that is what i have come up with so far... To answer 5614; Vibrational transitions can be accompanied by rotational transitions. and Electronic transitions can be accompanied by vibronic transitions.
  2. Fair enough. I am not sure myself. I think it is highly unlikely, but I do not really know, which is why i ask silkworm what he was thinking of, since he made the above claim. Just curious is all, really.
  3. You are correct. However' date=' UV light excites an [i']electronic[/i] transition which is accompanied by a vibronic and rotational transition. I had ask for an example of a purely vibrational or rotational transition providing the requisite activation energy. The only example that I can think of that even comes close might be in some isomerizations (ie. switching between chair conformations in a hexane molecule) however, this is much more a physical process than a chemical process, which is what I think we were discussing.
  4. For swansont: Which molecular vibrational transitions are abosorb or emit visible light? Can you give an example? I can't think of any off the top of my head and would like to know what they are (cause that seems kinda cool -- so REALLY high energy vibrations).
  5. If you can provide me with a list of chemical processes that are affected by light that excites purely vibrational/rotational transitions' date=' then sure. I will accept that given enough infrared light, one can heat up a reaction to the point that you have supplied the requisite activation energy, however,.... emphasis mine -- reading "the vibrations it causes can do useful work overcomming an activation barrier" So, i would love to hear some examples where purely vibrational events provide the activation energy or lead to decomposition. I am not saying that it doesn't happen, just that I know of no examples were it does...
  6. if it provides the activation energy, then it MUST affect the rate of the reaction, by definition. consider this, DNA is a fairly stable molecule and left in liquid it will retain the phosphate backbone linkages for a fiar amount of time (days). However, if you put DNA into a sonicator (a water bath through which high energy sound is pumped), you can break it up into many tiny pieces, effectively speeding up the process of degredation (breaking of the phospate bonds). So, yes, sound can affect the rate of a reaction. I cannot think of anyway that sound would effect the equilibrium of a reaction (at least not of the top of my head) but that is a very interesting question. I will think more about it.
  7. VendingMenace

    mass

    Not true. Light only travels at c in a vacum. When a photon is passing though any other medium, then it travels slower. Ie. light travels slower through glass, and different wavelengths are slowed differently. This is why a prisim splits light into a spectrum. What we know from Eistein is that nothing can travel faster than c. In fact, we don't even know this. What we know is that nothing initially traveling slower than c can be accelerated to a speed faster than c.
  8. dude, that sounds like a great assignment, pogos. Seriously. Of course i kinda felt the same way when i was in HS. It wasn't until i was starting grad school that my eyes were really opened to what was going on in literature. Now i love the stuff. It is funny how your opinons and thoughts change over time. On another note, i think it is a good idea to have classes that are subjectively graded. Not everything in life is objective. You will have bosses that tell you to do things their way, just becuase, and you had better figure it out or theguy next door is going to get the raise/promotion/recognition. English and art classes in HS are a great way to learn how to "read" an athority figure and be able to produce what they want. perhaps not the most rewarding thing you will ever have to do, but a good skill to posess nonetheless.
  9. x axis has the non imaginary parts while the y axis has the imaginary parts. So if you have a number 25 + 32i you would graph a point at (25, 32i). Does that make sense?
  10. no, i don't think it is a sociophobia or anything like that. Agrophobia is simply the fear that you cannot get to somewhere "safe." At least as I understand it. Thus, large crowds can trigger it, because it would most difficult to find a place away from the crowd. It is not nessesarily that you are afriad of the individuals in it, per se, but rather that there is no way to get away from the crowd and to somewhere safe. I think that crowds in general trigger lots of phobias. Social ones, agrophobia, claustrophobia, and people with illness/germ phobias as well.
  11. not true' date=' there are [b']five[/b] choices a) monera b) protista c) Fungi d) plant e) animal last three are pretty self explanitory, i think. THe first one is unicellular organisms with no nucleus the second is unicellular (mainly -- some of them form collonies ie. algea) organisms wich have a nucleous. just wanted to clear that up
  12. sure thing.... Ok, so you have 32 amino acids and you need to code for each one of them. That means that you need to be able to make at least 32 disinct DNA sequences. Stipulated in the question was that there are only two different DNA bases (let's call then base A and base B). Thus, for each position on the DNA you have two choices (base A or base B). With me so far? Ok then, if we were to consider a stretch of DNA 1 base pair long, we would have two choices, either A or B. if we were to consider a stretch of DNA 2 base pairs long, we would have 4 choices, AA AB BA BB if we were to consider a stretch of DNA 3 base pairs long, we would have 8 choices, namley; AAA AAB ABA BAA ABB BAB BBA BBB ok, so, in general, if you take a sequence wich is N base pairs long and you have X number of base pairs to chose from and you are allowed to repeat your choices (ie. the string can have mulptiple of the same base) the formula for the number of possible permutations is; X^N in this case we see that if we have two base pairs, then a sequence of 5 bases will give us 2^5 or 32 different permutations. However, we require to be able to code for 34 ammino acids. Thus, we need at least 34 unique permutations. So, the sequence needs to be longer. If it is 6 base pairs, then it would have 2^6 = 64 possible permutations and would be able to code for 34 ammino acids. Cool. I hope that makes sense. Let me know if it was unclear anywhere or if you need more information. ;D
  13. Well, just a quick guess, let me know if you want explinations rather than verification 1)6 because 2^5 = 32 <36 so it must be 2^6, wich gives 64 possible combinations, enough to code for 34 ammino acids 2)They lower the activation energy of a reaction 3)Adhesive forces (ie. the molecules wish to stick to the tube quite abit) i could be wrong here, just a guess. 4) I have no idea.
  14. Ok. So i think physisics know that the universe just interacts as it does. But what the uncertainty priciple says is that there is only so much that is possible for us to know about at anygiven time. Indeed that there is only so much for ANY observer to know about at any given time. It is a statement about how precisely a certain set of quantities can be measured. So, indeed, there does exist uncertainty -- even only if it is for our own measurements. Saying that uncertainly does not exist is irresponsible. For clearly it is a limitation that is quite real for us. Of course, the interesting (and metaphysical) thing emerges when you try to define what an "observer" is. It could very well be that the universe's other particles are also observers, and then the universe itself would be constrained in its interactions by the uncertianty principle. I really don't see what problem you have with the universe having an uncertianty priciple. As you said yourself; "There is the interaction of the universe." Why must it be that the universe's interaction cannot include and be constrained by such uncertainty? I see no reason to require that there is no uncertianty. I am afraid that i don't get what you are driving at here. Could you please explain more? Thanks Yes, quantum effects are much more readily apparent as you decrease the mass/energy/size/ect of the system. But just because these properties normally emerge at a different level than you are used to living at does not mean that that they don't exist. Without quantum, how do you explain the line spectrum of stars or the work function of a metal, both of wich are macroscopically observable? ?? This just seems quite silly. Why can't i predict what you will do tommorrow morning? The answer is simple. YOu don't exist. Proton head is just a construct that i came up with becuase the idea is helpful. But you do exist. The validity of my assinging you as Proton head, is repeatedly verified by the usefulness of that construct. Perhaps electrons do not exist in exactly the way that we describe them right now. IN fact, most assuridly we are wrong. However, this does not mean that there are not electronically negative particles in the universe. If there were not, then how would be account for discrete changes in charge? I know you seem to have a problem with discrete things, but i will get to that next. It most certainly is not. Again, i point you to the line spectrums of the stars. Or to the fact that the universe is not just one large baseball. IN fact, on our world alone we have many baseballs. If the universe was completely continous, there would be no way for seperate baseballs (or seperate anything) to exist. It would all be one large globby thingy. If discreteness can exist on a macroscopic scale (ie. seperatable, countable, objects) why would one disregard it on a microscopic and moleculare level? Why does measuing from inside the system yeild our results invalid? Well, i am sure that some people do make stupid claims about the universe, baised on physics. However, i am not quite sure that non-determinism is one of them. I see no reason whatsoever that one would need the universe to be deterministic. A universe that is ruled by statistical laws would work just as well as one ruled by newtonian laws. And the former would not be deterministic. But in the end, i suppose it is impossible to PROVE one way or the other. I guess there will always be uncertianty in people's minds and they will just end up believing what they choose to (or are forced to -- in a deterministic universe).
  15. Ok. So i think physisics know that the universe just interacts as it does. But what the uncertainty priciple says is that there is only so much that is possible for us to know about at anygiven time. Indeed that there is only so much for ANY observer to know about at any given time. It is a statement about how precisely a certain set of quantities can be measured. So, indeed, there does exist uncertainty -- even only if it is for our own measurements. Saying that uncertainly does not exist is irresponsible. For clearly it is a limitation that is quite real for us. Of course, the interesting (and metaphysical) thing emerges when you try to define what an "observer" is. It could very well be that the universe's other particles are also observers, and then the universe itself would be constrained in its interactions by the uncertianty principle. I really don't see what problem you have with the universe having an uncertianty priciple. As you said yourself; "There is the interaction of the universe." Why must it be that the universe's interaction cannot include and be constrained by such uncertainty? I see no reason to require that there is no uncertianty. I am afraid that i don't get what you are driving at here. Could you please explain more? Thanks Yes, quantum effects are much more readily apparent as you decrease the mass/energy/size/ect of the system. But just because these properties normally emerge at a different level than you are used to living at does not mean that that they don't exist. Without quantum, how do you explain the line spectrum of stars or the work function of a metal, both of wich are macroscopically observable? ?? This just seems quite silly. Why can't i predict what you will do tommorrow morning? The answer is simple. YOu don't exist. Proton head is just a construct that i came up with becuase the idea is helpful. But you do exist. The validity of my assinging you as Proton head, is repeatedly verified by the usefulness of that construct. Perhaps electrons do not exist in exactly the way that we describe them right now. IN fact, most assuridly we are wrong. However, this does not mean that there are not electronically negative particles in the universe. If there were not, then how would be account for discrete changes in charge? I know you seem to have a problem with discrete things, but i will get to that next. It most certainly is not. Again, i point you to the line spectrums of the stars. Or to the fact that the universe is not just one large baseball. IN fact, on our world alone we have many baseballs. If the universe was completely continous, there would be no way for seperate baseballs (or seperate anything) to exist. It would all be one large globby thingy. If discreteness can exist on a macroscopic scale (ie. seperatable, countable, objects) why would one disregard it on a microscopic and moleculare level? Why does measuing from inside the system yeild our results invalid? Well, i am sure that some people do make stupid claims about the universe, baised on physics. However, i am not quite sure that non-determinism is one of them. I see no reason whatsoever that one would need the universe to be deterministic. A universe that is ruled by statistical laws would work just as well as one ruled by newtonian laws. And the former would not be deterministic. But in the end, i suppose it is impossible to PROVE one way or the other. I guess there will always be uncertianty in people's minds and they will just end up believing what they choose to (or are forced to -- in a deterministic universe).
  16. the difference is that the body can use ATP later on down the road to do something useful. The energy lost to heat is just dissipated and cannot be regained. (though of course it is nessesary to keep your body warm to some degree, so i guess it is not entirely pointless). Think of it this way... Making ATP is like making a battery. It takes energy to make it, but once you have it, you can use it later to something else you might wish to do. Loosing heat is like running the heater in your house with all the doors open. Sure, it will heat your house some, but pretty quickly the heat will escape and you will never again see the energy you put into heating your house. It is totally lost. Does that help?
  17. the difference is that the body can use ATP later on down the road to do something useful. The energy lost to heat is just dissipated and cannot be regained. (though of course it is nessesary to keep your body warm to some degree, so i guess it is not entirely pointless). Think of it this way... Making ATP is like making a battery. It takes energy to make it, but once you have it, you can use it later to something else you might wish to do. Loosing heat is like running the heater in your house with all the doors open. Sure, it will heat your house some, but pretty quickly the heat will escape and you will never again see the energy you put into heating your house. It is totally lost. Does that help?
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