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Everything posted by grifter

  1. what makes you think it is the wrong way around, from what you have descried "a viscous liquid" this is definitely NOT H2O2 as this is not that viscous only a little more that H20 it also has no odor as oppose to Phenyl group which is aromatic. crack open the glass and test for H2O2 by adding some manganese dioxide, else some potato, (you may laugh but it's a brilliant cat) if u get "bubbling" then you have H2O2. hope this helps
  2. well I'm 1/4 if the way through the 4 week lab time and I'm already half finished, this leads me to question 2: any ideas on how to expand the practical.
  3. yea, yea it is, but I've got it figured now, I just have 30 hours of lab time to botch-together an experiment
  4. Yea JC if I knew what I was on about it would help, but since My retarded question gained little response I will post my findings below, to aid anyone else in the unfortunate position of having to do this Experiment: Raoult’s law states: The vapour pressure of an ideal solution is dependent on the vapor pressure of each chemical component and the mole fraction of the component present in the solution. Vapour pressure of a solvent in an ideal solution = the mole fraction of the solvent x the vapour pressure of the pure solvent. Vapour pressure varies with the strength of the intermolecular forces in the liquid. The Chemicalls I'm gunna use are the following (N.B.) ideal means it demonstrates how an ideal solution behaves according to Raoult's law +ve means it shows positive deviation, and i bet you can work out for yourselves what the -ve stands for... 1) Benzene + toluene (AKA methylbenzene)(ideal) 2) Trichloromethane(CHCl3) + ethoxyethane (-ve) 3) ethanol + water (+ve) as far as method is concerned, well, its surprisingly easy! make up a number of solutions i.e. 100%A 0%B 75%A 25%B 50%A 50%B 25%A 75%B 0%a 100%B heat under reflux with anti bumping granules etc etc and record the boiling temp after that it becomes pretty apparent. just draw up a graph with %soln on X-axis and temp on the Y-axis Job done ! I hope someone in need finds this in a few years time and appreciates it, i sure know i would have ! Oh and if anyone wants explanation on why these particular chemicals show these trends PM or email me, or carrier pigeon...
  5. lol, Thanks for your response, I guess this is too specialized for you guys (thats meant to enrage you to the extent at which you must post in order to prove your knowledge) feel free to post below...
  6. BUMP for the third time, perhaps this post could win some sort of "least replied to" award!!! I would really appreciate some help, come on guys !
  7. Well as I'm sure most of you will know I'm more of a Physicist than a Chemist, so, please excuse the rookieness: Okay I'll cut to the chase; I intend to carry out an experiment regarding Raoult's law and its variations, i would love some pointers, I need to prove the Law and its variations i presume for A-A A-B and B-B solutions (some explanation on wtf those are might be nice too ) I presume (notice, there are lots of presumptions going on here...) that i need an Ideal solution (or 10 of them...) and maybe a few that nicely show the variations of the Law. I know that the solution should be very dilute, (but i figured, if it was too dilute i might as well just investigate saturated vapor pressure which i don't want to do...) as you can see I need help on this one... anything you think might help would be most appreciated !!! BUMP sorry but I'm getting desperate here ! Bump & Update Okay, since I made this post I have asked arround elsewhere, as I have had 0 response from you guys! But hey, you get what you pay for....right anywhoo, i have decided on a method, which is to mix different volumes togeter i.e. chemical X and Y 100%X 0%y 75%X 25%Y 50%X 20%Y 25%X 75%Y 0%X 100%Y Then produce a graph. Hopefully ideal(ish) solutions will provbide linear lines for bpt and non ideal's will skew somewhat! now all i need is my other questions answerd, i.e. what solutions to use...
  8. Martin, did you not hear about the pre-mission prep team that went up ahead of the main mission to add some flagstones and a nice gazebo they're thinking about some crazy-paving for Jupiter, i think it would be a nice touch on a more serious note, those are some brilliant images, I wonder if the nice chaps at NASA would let me have a drive ??
  9. Hey Martin (and others ) yep 8A is correct, Granulation is right! it gives the suns visible surface a grainy texture (hence the name...) I hope you ace the test oops i mean get full marks in the homework, oh sorry i mean do well with the "study guide" (I'm just "yanking your chain")
  10. ^ what he said, if the product isn't "as specified" then i hear the sound of compensation ! so long as it doesn't say "contains chlorine" anywhere,which i guess it doesn't......or you wouldn't have brought it..
  11. hmm, electrons "orbiting" a nucleus, this is a common misconception, (I'm going off the point here...) we have to think of electrons in an atom as a "cloud" in fact, it is commonly referred to as a probability cloud, which put simply denotes that electrons are "smeared" around the nucleus. which leads to other fascinating properties of electrons, but thats for another article
  12. hey, can we try and keep this clean and science based, I pretty sure this section of the forum is based around physics, I think "d1c4 head" belongs in the biology forum, you never know, if your lucky, you might have a paper written on you, regarding this phenomenon....
  13. foodchain had some good points there, I 'm inclined not to help you, just out of spite as I'm rather jealous, but what the hell, for the good of the forum: Now; you need to get a clear definition of "ecosphere," in a biological sense an "ecosphere" is simply a global ecosystem, but in astrophysics it is a "shell" that surrounds a star which has the correct parameters to sustain life, yet creating the latter would be ...impossible or at least without "creating a star" I Will presume you are referring to the former (you may consider posting in the biology section for some more info on a BIOSPHERE) things to consider: 1./ source of energy, almost certainly "reusable-energy" (whatever that means these days) this will eliminate any cox 2./ natural resources, I would strongly recommend terraforming (http://en.wikipedia.org/wiki/Terraforming) 3./ don't forget the basics i.e. size of planet, orbital parameters, after all you don't want to spend billions terraforming only to realize your stuck on a Pluto-like planet, e.g. you will want your planet to be in (as discussed earlier) the habitable zone, which for any given star can be found with this equation: [math]d_{AU}\,\,\,\ \sqrt{L_{star}/L_{sun}}[/math] Where: [math]d_{AU}[/math] is the radius of the habitable zone [math]L_{star}[/math] is the luminosity of the star (biometric luminosity) [math]L_{sun}[/math] is the luminosity of the sun (bolometric luminosity) once you have considered a HZ (habitable zone) in the solar system you need to think about the solar systems location in its galaxy, you need to be close enough to the centerer for heavy elements to exist, you also have to be far enough away from the center, to avoid being devoured by your local neighborhood super massive, or be ionized to the extent that humans grow a third eye, anyway, just something to think about, good luck
  14. right well, the exams are out of the way (finally) Gravitational waves: there is a neat equation that calculates power flux where: the gravitational wave has a strain [math]h[/math] and frequency [math]f[/math] [math]F= \frac{c^3 \pi f^2 h^2}{G}\,\,\,\,\,\,\, Wm^{-2}[/math] sticking some values in to this [math]h = 10^{-22}[/math] [math]f = 280 \,\,\, (Hz)[/math] to put this in to perspective: F is equivalent to the signal from a mobile phone at a distance of 15m or a mg -11 star (moon is ~12.7) this may make you wonder why we don't hear more about gravitational waves, there is a simple reason for this: Spacetime itself is very "stiff" a signal that carries a large power @ the above frequencies generates only a small strain this would be no problem if we had detectors that had a similar stiffness, we could, therefore measure the large induced stress, but currently our detectors are strain-based so need to work very hard, but a new generation of detectors are being built (discussed in the article) this is a pioneering area of physics, and I'm watching it with GREAT interest. great things are going to happen, mark my words !
  15. you don't by any chance receive, astronomy and geophysics??? they had a sterling article regarding the recent advances of gravitational astrophysics, but I can't find my issue (April (I think) 2007, Vol-48, Issue-2)I referenced it one before...thus I know the issue No e.t.c. But I will post some more tomorrow (when I have finished my final two physics exams)....finally
  16. well, any tactical weapon is designed for use in a war, as oppose to a deterrent.. and hybrid implies that it is modified, and in someway combined with another device; so, a "hybrid tactical nuclear weapon" would imply a "nuclear class" modified weapon for use in combat situations it may be referring to the fission-fusion-fission bomb, which combines (as the name suggests)fusion and fission devices
  17. not to mention the human inhabitants...
  18. you might want to check this out (http://www.freepatentsonline.com/4827050.html), sorry, i cant write any more, i need to revise for an exam...
  19. Swansont, I was just thinking the same, what is this ''between electron shells'' are you refering to the forbiden gap ? If so, I dont know what relivance it has in this situation...
  20. sulphur emits a blue flame when burnt (and becomes a red liquid, good for tricking teachers, ahh sir I've cut myself) I think you may have been burning sodium as oppose to sodium nitrate, as under the old flame test sodium burns a vibrant yellowey orange... as oppose to sodium nitrate which is un-flamable
  21. thats, just cool, just think if we could do that, really cheap plane flights, no landing taxes, just, maybe, falling tax ?
  22. Yes the Bohr model is old, but thats the only way I could think of to find a value for velocity... but as Klaynos and I have stated......the electrons have no velocity, this dated model is you r best bet, I forund the value like so : [math] \frac{Kq_e^2}{r} = m_e v^2 [/math] to find v use this::: [math]\frac{k q_e^2}{n \hbar} = v[/math] where: [math]\hbar = \frac{h}{2\pi}[/math] [math]n =[/math]1,2,3,4 (quantum number) [math]q_e = [/math] charge on electron [math]k = \frac{1}{4 \pi \mathcal{E}_0}[/math] now for a bit of math [math] \frac{2.55 \times 10^{-42} \times -1^2}{1 \times 1.05\times10^{-34}} [/math] [math]\frac{2.55 \times10^{-42}}{1.05\times10^{-34}}[/math] and yes: [math]\frac{2.55 \times10^{-42}}{1.05\times10^{-34}} = 2.42\times10^{8} [/math] okay?
  23. We tend to think of electrons in atoms like planets orbiting the sun. While this view can often be useful, the first theories of atom structure by Bohr, is a gross simplification. The electron should be considered as smeared out over a large volume surrounding the atom. In this sense, the electron does not move inside the atom, as Klaynos has pointed out But still it is possible to ascribe approximate velocities to electrons in bound states. This is done to ascribe whether relativistic effects are important in calculating said bound states e.g. relative contraction of the inner core of electrons is normally used to explain some of the properties of transition metals, and relativistic corrections to calculations, are currently a pioneering physics. A gross model for "speeds" of electrons in bound states can be obtained from the Bohr model. This model predicts the electron (associated with a hydrogen nucleus) is moving at 2.42 x 108 cm sec-1 (ground state) this is pretty small compared to the speed of light... BUT I MUST STRESS (notice I'm stressing, because I'm using capitals ) AS I SAID ABOVE KLAYNOS IS CORRECT, THE ELECTRONS ARE NOT MOVING....
  24. Okay sorry, I have just repeated what ecoli said, sorry... I guess thats what happens when there's a topic everyone cant wait to share information on, and YT - thats funny ha ha
  25. these bonds between molecules are called intermolecular forces,and come in different strengths, which is why some things are harder to break than others, i.e. a hydrogen-bond is the strongest (like the one occurring is water) and an instantaneous dipole - induced dipole is one of the weaker forces, which is why for instance polymers with id-id bonds are very weak. these intermolecular bonds occur when the charges are unevenly distributed within a molecule. for id-id these molecules are unpolarized. For Hydrogen bonding there will be an electronegative atom and a hydrogen atom bonded to another electronegative atom.
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