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mississippichem

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Everything posted by mississippichem

  1. If I got offended every time my boss used ridicule to correct my thinking...I would've been fired long ago. Given, the ridicule is executed without personal attacks. A bit of ridicule at some of my less than ingenius ideas serves to show how ridiculous the implications of my hypothesis are. I appreciate this benign ridicule as it makes me a better scientist; wiser and more rigorous.
  2. The complex conjugate of a complex number is another complex number with the same real part and an oppositely signed imaginary part. For example the complex conjugate of 2-3i is 2+3i. Try to multiply any complex number with its complex conjugate. What do you notice about the result?
  3. The wavefunctions can in theory be complex valued. So the "psi squared" is really just the real equivalent of some complex valued psi times its complex conjugate.
  4. I imagine you're right and it just forms a copper acetonitrile complex with an iodide counter-ion.
  5. I think I have a demonstrative example of your sentiment here. The lab I work in collaborates with a computational physicists (We make materials with tuned dielectric properties). I was recently talking to one of our collaborators about how much programming he knew and he informed me that they have one guy who is a full fledged computer scientist and the rest of the team knows little programming. Thats not to say that extensive programing knowledge isn't useful. I think the labs of the future, in all disciplines, are becoming increasingly digital and will require scientists to become increasingly computer savy. If I knew more programing I feel like I could more efficiently operate some of the finer points of some of the spectroscopy units we have. I've seen people dial in specialized NMR experiments before straight from code.
  6. Shame that heavy leptons have such short life times. Mu-mesmic hydrogen would make for some really interesting NMR (nuclear magnetic resonance) experiments as there would be some wacky shielding effects. I've always fantasized what chemistry would be like if there was the possibility of stable heavy lepton bonds.
  7. Its great that you're curious about such things at a young age. Keep learning more physics and mathematics, you'll get to the point where you'll be able to consider things such as relativity. Just remember to always take to heart the advice of those more experienced (which you seem to be doing). Do these things, and I can almost promise that you'll be able to rub elbows with PhD physicists in your lifetime. The journey is long and hard, but well worth it. The man who thinks he is finished learning should just go die .
  8. How do you explain the net magnetic dipole moment of the electron? Or the net Coulombic charge on protons/electrons? Spin pairing of electrons in opposite spin states is observed. You must account for this in your model.
  9. In my city they fixed a similar problem by requiring that people have a license to sell copper, obtained by presenting a tax ID number and a brief description of how your business is involved in the copper industry.
  10. According Housecroft's Inorganic Chemistry alpha-alumina (corrundum) displays a hexagonally closepacked lattice with oxide ions occupying two thirds of the octahedral interstitial sites. While gamma alumina has a defect spinel lattice. Of course this goes for bulk alumina so I don't know how applicable this would be to an oxide layer on the surface of bulk Al(0).
  11. I imagine you'll get banned before we get to hundreds of topics.
  12. I usually call them Jim, John, and Terry. Terry is recently divorced though and doesn't feel like talking much anymore.
  13. Nasty, Nasty! I don't think all these pesky physicists [they've taken over the staff, definitely a conspiracy] are ready to see that yet. They might keel over and die at the mighty awesomeness of the rotaxane insertion. Men with smaller R-groups also get intimidated by women who proudly expose their macrocycles. *anyone who doesn't follow this should google rotaxane and look at pictures to catch the innuendo. Shield your eyes children.
  14. Right. There is no theoretical limit on how much chemical energy can be put off by a reaction. Though I think we are already near the practical limit (just my opinion). Alkanes (major component of gasoline, diesel, etc.) are already quite energy dense with respect to combustion. Octane (an alkane with an eight carbon chain) has an enthalpy of combustion of about 5000 kJ/mol which is huge. Luckily alkanes are stable (kinetically anyway) at room temperature and atmospheric pressure. Fuels that have higher enthalpies of combustion such as boranes or hydrogen/oxygen mix are practically an explosion waiting to happen. H2/O2 on ploymer support with AlClO4 has already been used as a rocket fuel and is extremely energy dense, however fuels like this will simply never be safe enough for you to fill up the family sedan with. I think the fuels of the future will not be advantageous based on their energy density. Instead they will be advantageous based on their sustainability (think solar, and hydro-electric; the collection methods are all "passive"). To really make order of magnitude differences to how much energy we can get out of a one meter cubed box, we'll need to look to nuclear processes or other exotic things. I find this to be a strangely provocative (in the good way) question by the way. A very good first first thread for you. Welcome to SFN.
  15. There is no theoretical limit on how exothermic a reaction can be. As far as percent energy that can be extracted to do work...you are limited by the Carnot efficiency. The second law in a way limits the amount of energy you can harvest as work from a system. For a reversible process: [math]dS=\frac{dq}{T}[/math] [math] \oint \frac{1}{T}dq \leq 0 [/math] If we play around with entropy and the other state-functions we can get: [math]dG=Vdp-TdS [/math] and therefore, [math] dG=\frac{\partial G}{\partial p}dp + \frac{\partial G}{\partial S}dS [/math] Gibbs energy (G) is a measure of spontaneity, and therefore a measure of the amount of energy available to do work. Here I've expressed the Gibbs energy as a function of pressure and entropy only, so one can see that the amount of energy we can extract is really only limited by how low we can get the pressure and how large we can make the change in entropy. Of course practically we are limited by how unstable of a reagent we can have. The decomposition of [ce]CH_{5}^+[/ce] would in theory be hugely exothermic as well as hugely entropically favored but doesn't happen [measurably] because one can never isolate such exotic compounds in the first place. All this rant to say that there is no theoretical limit to the amount of chemical energy we can extract from a 1 meter-cubed box, but practical limitations are very real. There are some hugely energetic materials out there. But the scale of chemical reaction energies is smaller than that achievable by nuclear or annihilation events by orders of magnitude.
  16. So...your place at 5:00 PM? I'll bring the beer if swansont will bring a laptop so we can go on a drunken banning spree.
  17. Logical fallacy: early victory. You've framed abortion as murder in your argument when the ethics of abortion is the topic at hand. You've effectively stated that abortion is bad because abortion is bad. Do you still beat your wife?
  18. Someone who joins an internet forum in order to critique the mental health of its staff, in my opinion, himself needs psychological assistance. People come to a science forum to discuss science. People who don't won't to discuss things in a scientific manner tend to get banned. All moderator action on this forum is first discussed amongst the staff so there are checks and balances. Tell your recently banned friend to find a religion forum. By the way thanks for joining and boosting our google analytics numbers
  19. Oh. Utrafilterable! I stupidly read "unfilterable". Disregard my hastily posted comment above.
  20. I think that whether our not the silicon atoms gets bitten depends on the nuclephile. I think a small, sterically unhindered "hard nucleophile" might go for the Si atom. But, as hypervalentiodine said that planar electron deficient carbon atom is a very attractive target for a nuclephile. In this case I think the Si atom attack will happen minimally. If the Si atom was surrounded by -OH groups and that carbon wasn't so electron deficient then I could maybe see it. I do a reaction in my work where I sub out a methyl ether for an ethyl ether on an electron rich Silicon atom though (yes electron rich, strange right?). We have to use a Dean Stark trap to drive the equilibrium though, and the reaction is quite slow for a terminal substitution. Reactions at silicon atoms can be quite counterintuitive as the electronegativity is similar to carbon but the orbital energies are not and the polarizability is not.
  21. Some nanoparticle solutions can't be filtered by traditional means. They'll either conglomerate and fall out of the colloidal phase our slip right through the filter. Could this be what you are talking about?
  22. I know that chemistry and computer science will require some degree of mathematical prowess (though not as intense as physics or mathematics but still more in depth than other non-science fields).
  23. Or single molecule fluorescence. One measured photon in, one measured photon out. The existence of darkons would make all spectroscopy fail miserably.
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