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Why would white phosphorus burn flesh bu not clothes?

  1. Nov 9, 2005 #1
    I have seen this claim in the Italian documentary about the use of WP in Fallujah. However I don't understand how this is possible.

    Can anyone here explain this?
     
  2. jcsd
  3. Nov 9, 2005 #2

    cronxeh

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    When white phosphorus burns:
    P4 + 5 O2 → 2 P2O5

    The formed phosphorus pentoxide absorbs water from your tissues and quickly converts into phosphoric acid which then burns your skin:

    P2O5 + 3 H2O → 2 H3PO4
     
  4. Nov 9, 2005 #3
    Thank you very much. That explains a lot.
     
  5. Nov 9, 2005 #4

    Bystander

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    --- and, organic fibers in common textiles being refractory are unaffected by any of the heat released in such reactions --- WP is an incendiary --- of course it's going to burn the garments. Now, before I call the mods to lock this thread, what other processes are likely to make week old corpses look like week old corpses --- particularly in that part of the world? Can you say "putrefaction?"
     
  6. Nov 10, 2005 #5

    ShawnD

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    That still wouldn't explain why it doesn't burn clothes. I've had 40% phosphoric acid spilled on my lab coat, and trust me, that stuff completely destroys clothes.
    P2O5 also pulls water from the atmosphere, so it can turn into acid without even touching your hand.
     
  7. Nov 10, 2005 #6

    Pengwuino

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    I've also used phosphoric acid and it was very clear that you did NOT want to get that stuff on your clothes.
     
  8. Nov 11, 2005 #7

    cronxeh

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    If it takes place in vivo then there is no point for acid to react with clothing - the acid will attack organic matter and react with the tissues since the P2O5 would pull water from your tissues and not from the clothing. the amount of water in the atmosphere is negligeble compared to that found in the lungs and tissues - therefore the burning P4 as well as P2O5 will react violently in vivo - burning the skin all the way down to the bone from outside and the lungs and trachea, bronchi, and alveoli from the inside. Dont forget the fact that there is a rate of positive air movement due to breathing at about 12 a minute, so if you are exposed to the cloud it will get inhaled and exposed to your skin the most as compared to your clothe. I cant come up with a counter argument as to why it would even burn the clothe in the first place as there is simply so much tissue to react with!
     
  9. Nov 11, 2005 #8

    Bystander

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    Okay, sport, I told you to keep the "make it up as you go along" routine in the "whine cellar" where this question came up.

    You want something simple? Here's something simple: http://en.wikipedia.org/wiki/White_Phosphorus

    Take your confabulations elsewhere.
     
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