Search results

  1. C

    Nanotubes in Electric Field

    Or, alternatively, is it because the charges at the each end of the nanotube will be closer to the electrode of the opposite charge?
  2. C

    Nanotubes in Electric Field

    Conducting carbon nanotubes align their primary axises in the direction of static electric field. Why is this? I am thinking that it's because since this is their longer axis, the gradient of the generated electric field within the nanotubes will be less than in the perpendicular case. Is this...
  3. C

    Outputting Voltages to a Computer

    Thanks both of you for your help. I just wanted to make sure I was looking at the right type of product before buying something. All I want to do is read the data and be able to record it eventually with something like Excel.
  4. C

    Outputting Voltages to a Computer

    First off, I had no idea in which subforum to post this, so moderators feel free to move this if appropriate. I have an old oxygen sensor (electrode) which outputs a DC voltage ranging from 1-5 V which has no interface to a computer. So I was wondering if something like this-...
  5. C

    Refractive index of Vanillin and p-bromobenzophenone

    Probably safe to assume 25C.
  6. C

    Fuel Consumed by Oil Refineries

    Hi everyone, I was looking at some data from the Energy Information Association (http://www.eia.doe.gov/emeu/mecs/mecs2006/pdf/Table3_2.pdf\) about the fuel used by different industrial processes. Under the industry of "Petroleum Refining," there is a bit of natural gas and electricity used...
  7. C

    This problem is killing me [calculation of electron transition]

    2.18x10-18 is the Rhydberg constant in joules.
  8. C

    Why does hot water are white?

    Why does hot water have more air bubbles than cold water?
  9. C

    NaHCO3 Electrolysis Products

    Nothing would happen to the sodium- it just stays in solution as Na+. Cu+2 ions can be very deep blue.
  10. C

    NaHCO3 Electrolysis Products

    Copper hydroxide
  11. C

    Differential v. Integral Rate Laws; Kinetics

    Although this is a differential equation, it is a very simple one to solve. In fact, the other simple rate laws (k[A]2 or k[A]3) are easy to solve as well. It only gets difficult when you include [A] and [B] In order to solve this just integrate (still beyond precalculus level though)...
  12. C

    How to seperate c02 from air?

    Use something like NaOH, KOH, Ca(OH)2. These will react with the CO2 in the air to give the corresponding bicarbonates/carbonates. They won't react with N2, O2, or Ar. Then dry the carbonates in an oven to get rid of the water and then heat them up to decompose them into CO2.
  13. C

    Dissolving plant matter

    Have to deal with heavy metal waste then. Also it's unlikely a nonchemist would have access to these materials. Concentrated sulfuric acid (98%) is sold in drain cleaners and is something that the general public does, in fact, deal with. One can carefully neutralize H2SO4 with bicarbonate to...
  14. C

    Simple Cubic Crystal

    The length of a unit cell is usually define as a. Volume should be simple from this. For the volume of atoms, take a look at how much of each atom is in the cell.
  15. C

    Dissolving plant matter

    Concentrated sulfuric acid would probably work well. A "Piranha solution" composed of hydrogen peroxide and sulfuric acid is even better and will dissolve almost anything. Note: You need to be extremely careful with these types of solutions. Since they can dissolve the organic matter of plants...
  16. C

    Cannizzaro reaction lab

    Depending on the aldehyde and reaction conditions, this reaction might not go to completion and so you'll be left with some aldehyde.
  17. C

    Silver nitrate + water ? / Br in water?

    And you were judging this just based on precipitate color? This doesn't seem like a very definitive method of analysis.
  18. C

    Oxidizer strength

    Isn't this entirely dependent upon the anion in question? I would think, in general, when you are comparing cations of similar electronegativity, ion pairs of similar size would be stabler because this would allow for better crystal packing. If we use melting point as a metric for stability (we...
  19. C

    Oxidizer strength

    Yeah good point. O2 from air is the oxidizer in this case. So I should have asked: Why is O2 a more potent oxidizer in molten KOH than NaOH? Or alternatively, as you hint at, there might be some difference in the stability of the Na2MnO4 and K2MnO4.
  20. C

    Oxidizer strength

    This is an excellent question samblohm! I don't have an answer, but will add to the puzzle. I've read things that seem to say that molten KOH is a stronger oxidizer than NaOH. Any idea on why this would be? NaOH only takes Mn(IV) to Mn(V) in this case whereas KOH takes it to Mn(VI). Why...
  21. C

    Hydrogen Sulfide and Hydrosulfuric Acid

    Me looks like methyl; M is generally used
  22. C

    The most difficult thing to do in the course Chemistry 1

    Pragmatically, solving equilibrium expressions was the hardest for me. There's often a lot of equations to chug through. Conceptually, I had trouble understanding where almost all of the quantum mechanics came from. Most of it is plucked from the air and has no context unless you have previous...
  23. C

    Isomers: Geometric and Diastereometric Isomers

    Diastereomers and enatiomers are both stereoisomers (isomers that have to do with chirality). Diastereomers are stereoiosmers that aren't enatiomers. Enatiomers are exact mirror images of one another- that is all chiral centers have opposite optical configurations. So in your example of two...
  24. C

    Anhydrous Chloride Salts

    Yeah, this sounds more or less like it'll work although I've never tried it. I'd been interesting in hearing how it works if you attempt this experiment. This might be of use to you. It's out of my library:
  25. C

    Why do we neglect the effect of conjugate base when measuring the pH of weak acid?

    1) CH3COOH(aq) + H2O(l) = CH3COO-(aq) + H3O+(aq) 2) CH3COO-(aq) + H2O(l) = CH3COOH(aq) + OH-(aq) 3) H3O+(aq) + OH-(aq) = 2H2O(l) ------------------------------------------------- net of 2 and 3: CH3COO-(aq) + H3O+(aq) = CH3COOH(aq) + H2O(l) which is the reverse of 1. So your second equation is...
  26. C

    Order of acidity in organic compounds

    The key to determining the acidity of a compound is to look at the stability of the formed anion. Consider here resonance structures and electronic effects.
  27. C

    Salt deposit deterrance by Magnesium rod

    I think the magnesium is acting as a sacrificial anode: http://en.wikipedia.org/wiki/Sacrificial_anode
  28. C

    Caustic soda

    Well, I know caustic soda is often used to clean ovens. It removes grease well.
  29. C

    Usage of Calculus in Chemistry

    Derivation of rate laws uses integration.
  30. C

    Calculating pKa when pH is known

    I think you idea is correct. You can definitely determine the pKa of an acid by titrating it with a base and using the Henderson-Hasselbach equation. Half way to the equivalence point of the titration, the pKa will be equal to the pH. This would be the best point to determine the pKa (smallest...
Top