Why would white phosphorus burn flesh bu not clothes?

  • Thread starter Skyhunter
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In summary, the conversation discusses the use of white phosphorus in Fallujah and how it burns when it comes into contact with oxygen and water. The resulting phosphoric acid can cause severe burns on skin and organic matter. The conversation also touches on the fact that white phosphorus can also burn clothing, and the reasons for this are debated. Some argue that the acid would primarily react with the organic matter in the body rather than clothing, while others suggest that the amount of water in the atmosphere is negligible compared to that found in the lungs and tissues. The conversation concludes with a request to stop speculating and for the individual to do their own research on the topic.
  • #1
Skyhunter
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?
 
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  • #2
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
 
  • #3
cronxeh said:
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
Thank you very much. That explains a lot.
 
  • #4
--- 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?"
 
  • #5
cronxeh said:
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
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.
 
  • #6
I've also used phosphoric acid and it was very clear that you did NOT want to get that stuff on your clothes.
 
  • #7
ShawnD said:
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.

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 can't 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!
 
  • #8
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.
 

1. Why does white phosphorus burn flesh but not clothes?

White phosphorus has a low ignition temperature and can ignite spontaneously in the presence of air. When it comes into contact with skin, it can quickly burn and cause severe damage. However, clothing acts as a barrier and can prevent the phosphorus from coming into direct contact with the skin, thus reducing the burning effect.

2. What is the chemical reaction that causes white phosphorus to burn flesh?

The reaction between white phosphorus and oxygen in the air produces a chemical reaction that releases a large amount of energy in the form of heat and light. This reaction is exothermic, meaning it releases heat, and it can cause severe burns when it comes into contact with human skin.

3. Can white phosphorus burn clothing under certain conditions?

Under certain conditions, such as high temperatures or prolonged contact, white phosphorus can burn through clothing. It can also ignite flammable materials, such as cotton, and cause them to burn and spread the fire.

4. Is white phosphorus dangerous to handle?

Yes, white phosphorus is highly reactive and can be extremely dangerous to handle. It is often stored and transported under water to prevent it from coming into contact with air and igniting. Proper safety precautions, such as wearing protective gear, should always be taken when handling white phosphorus.

5. Are there any other substances that can cause similar burning effects on flesh?

Yes, there are other substances that can cause similar burning effects on flesh, such as sulfuric acid and hydrofluoric acid. These substances are highly corrosive and can cause severe burns on contact with skin. Like white phosphorus, they should always be handled with extreme caution and proper safety measures.

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