Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How could i dissolve iron powder

  1. Mar 5, 2008 #1
    I want to make a standard iron solution 1 g/L by using iron powder and i can't dissolve it by any way. Is any one have an idea? thanks in advance.
     
  2. jcsd
  3. Mar 5, 2008 #2

    chemisttree

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    What form of iron are you after? Iron(0), iron(II) or iron(III).
     
  4. Mar 5, 2008 #3
    6 N HCl solution. Use it all the time to clean up flasks with iron residue.
     
  5. Mar 6, 2008 #4
    HNO3 dissolves iron quickly, but it doesn't have to be concentrated, you have to dilute it with some water (6N should be ok) or the reaction will be blocked by passivation. Be careful to red smokes of NOx, do it in a hood.
     
  6. Mar 6, 2008 #5
    Be careful with the nitric acid. I'm wondering if ammonium nitrate is a possible side product if you try to dissolve Fe with nitric acid. One chemist we had was trying to clean out his glassware of iron residue with nitric acid and caused a massive explosion. Luckily he wasn't hurt, but glass shards went flying everywhere. There were huge 7+ inch shards of glass embedded 8 inches in the wall.
     
  7. Mar 7, 2008 #6
    With an excess of iron it should be possible; it is, with excess zinc and HNO3. However, if NH4NO3 do really reacts in that way with HNO3, it should be, at least, dry.
    It's quite difficult for me to believe it was only Fe, NH4NO3 and HNO3, are you sure there wasn't something else, even in small amounts, in it?
     
  8. Mar 7, 2008 #7
    We don't know. There could have been some organic material in there as well. ANyway, we aren't allowed to use nitric acid to clean glassware anymore.
     
  9. Mar 7, 2008 #8
    Not trying to hijack your thread I just had a real quick question that isn't worthy or starting a new thread.

    Whats the difference between "solvating" and "dissolving"? I read that solvation is also called dissolution. Is dissolution just the process of dissolving? If I add salt to water I would be dissolving the salt in the water. Would I also be solvating the salt in the water or would I be solvating the water with salt?
     
  10. Mar 8, 2008 #9
    They are completely different cocepts.
    "Dissolve" means to bring something in solution, "solvate" means to make the molecules of that compound surrounded by water molecules, bound with some kind of weak bond, as ion-dipole, dipole-dipole bonds.
    If you dissolve NaCl in water you will also have solvation of Na+ and Cl- ions, that is every ion in water will react with H2O molecules forming a weak bond with them (with a variable number of water molecules, depending on the kind of ion, concentration, temperature, ecc.).

    In general you will always have more or less solvation, even if in some cases it could be so weak that you can neglete it; in that case you could have dissolution but with very little solvation; dissolution is a more complex phenomenon, that includes also solvation, in general (but not necessarily) but also other processes, that is the brokening of the salt's crystal, for example, and the increasing of the entropy due to the mixing solute/solvent.

    So, even if "solvation" do certainly affect solubility, it's different from "dissolution".
     
  11. Mar 11, 2008 #10
    it is a standard solution i think Iron(0) is correct

    ok i'll try and see

    6N HNO3? i didn't try to use it, thanks for the advice.

    thanks for the advice, and how is your friend now?

    !!

    !!

    it is ok my friend we all learn

    thanks for the information

    At the end and to be more clear i'll use this standard solution - after dissolving - to make a calibration curve for iron spectroscopic determination, now i'll try to use 6N HCL and 6N HNO3 separately of course and see.
     
  12. Mar 11, 2008 #11

    GCT

    User Avatar
    Science Advisor
    Homework Helper

    I'm curious to know exactly what is the iron powder that you're employing; how was it obtained? It could be one of the many forms of the hydroxide precipitate. One other way to dissolve iron into the solution is through electrochemistry methods.
     
  13. Mar 17, 2008 #12
  14. Mar 31, 2008 #13

    GCT

    User Avatar
    Science Advisor
    Homework Helper

    The link is not functional.
     
  15. Mar 31, 2008 #14

    chemisttree

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    If you are interested in dissolving zero valent iron, you should use iron pentacarbonyl. Sigma Aldrich product number 481718-25ML(100ML). Be careful, it's very toxic.
     
  16. Apr 11, 2008 #15
    i would go for simply, 5 ml. of dilute sulfuric acid then heating.. or mix of HNO3 & HCL then heating.. the last one should certainly dissolve it.
     
  17. Apr 11, 2008 #16
    Why the need to add HCl? HNO3 alone (not concentrated or Fe would be passivated) dissolves it well.
     
  18. Jan 28, 2009 #17
    hm. Not to change topic (I don't feel like starting a thread for small inquires) but isn't iron powder used in some military hand grenade. I do not remember, but I think it is used in either stun grenades or maybe in some napalm type grenade used in Vietnam. Yeah, cause when it reacts with "something" rust, it lets off heat strong enough to penetrate metal and can burn for hours.
     
  19. Feb 5, 2009 #18
    No, Ive heard of that too.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?