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What is the activation energy for a match?

  1. Aug 17, 2014 #1
    I saw a YouTube video where someone took nichrome wire and a high voltage source and managed to light a whole series of matches.

    I got me curious so I ran some numbers on how much wattage could be produced for a given length of nichrome wire and a given voltage. And assuming time is no issues you could leave said power source connected to the wire for as long as possible and in theory get a very high amount of joules of energy transfer, but exactly how much energy is required to ignite a match, couldn't find anything online anywhere with specific numbers.
  2. jcsd
  3. Aug 17, 2014 #2
    Most matches are made with potassium chlorate KClO3 as oxidizer and phosphorus sesquisulfide P4S3.
    2 KClO3 decomposes to 2 KCl and 3 O2, at 400 degrees C.
    Phosphorus sesquisulfide has a flash point around 100 degrees C, so once the oxidation starts, the P4S3 acts as the main fuel for the match. I think it decomposes to P4 and 3 SO2. P4, in turn, oxidizes to P4O10 in a complex, multi-step reaction. SO2 oxidizes to form SO3.
    Then, if there is water in the atmosphere, P4O10 + 6 H2O -> 4 H3PO4 (–177 kJ) making phosphoric acid. Also, SO3 + H2O -> H2SO4 (-88 kJ), making sulfuric acid.
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