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Thermite reaction on stove top?

  1. Oct 17, 2015 #1
    Gas stove with 16000 btu output and cast iron grate (non coated)---using an old aluminum pot (non anodized, etc). The grate has changed from black (no apparent rust) to a light gray color. Was there some type of low grade thermite reaction here?? Any comments or thoughts on this? Thanx
  2. jcsd
  3. Oct 17, 2015 #2


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    Staff: Mentor

    A lot depends on what you mean by

    But in general - no. Gas flame has different areas, reducing and oxidizing, that's perfectly enough to change the color on the iron grate.
  4. Oct 17, 2015 #3


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    Gold Member

    With the Thermit reaction, there is, in addition to metallic iron, the formation of aluminium oxide, which you do not mention seeing. It has been known for explosions to occur when an aluminium fuel nozzle is banged against a rusty iron tank filler.
  5. Oct 22, 2015 #4
    A thermite reaction once it starts is relatively easy to detect because in the redox reaction, fully consumes one of the reagents (rust) leaving behind molten iron. No rust, no thermite. Essentially, aluminum is burnt using the oxygen not in the air, but in the iron. But for this to occur, there has to be a good supply of rust and both it and the aluminum must be extremely granular to allow for the mixing of the two reagents so that the molecules of the oxide are close and readily available to the element. Remember that Al undergoes passiviation and the getting the reaction started to begin with is difficult and requires very high temperatures, like the burning of a magnesium ribbon.
    Last edited: Oct 22, 2015
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