I've seen this video in which fine iron powder reacts immediately with oxygen when exposed to the air, turning into rust.
Now, will this reaction always occur with iron powder? Or is there something special with this specific sample?
I'm writing a steampunk story where people are liberating iron powder in the air. Now, I know that iron powder exists without creating sparks, but I don't want to make some huge mistake, so I'd like to understand a little more about this reaction.
Also, the presence of coal combustion smoke or water steam would have some influence in the reaction?