Date: June 2006
Recently, I have come across an intriguing
discovery, powdered coffee creamer, when poured over a flame, can
be quite flammable. While conducting some experiments, I read the
back of pack of coffee creamer and it said, "Note, keep away from
an open flame, as with all powdered substances, the contents of
this packet are extremely flammable." I was wondering why this happens.
This only happens when the powder is poured over a flame giving the
powder room to spread.
In powders, there is a very large surface area to volume
ratio. Since the rate of reaction depends on available surface
atoms, when there is a large surface area to volume ratio, a reaction
can happen very quickly and even be explosive.
A 1-gram pellet of zinc is much less reactive than 1 gram of powdered
zinc. A large wooden log is much more difficult to ignite than a
similar amount of sawdust. Granaries have explosion hazards when
grain is transferred due to the dust that becomes airborne and
possible static electricity sparks. In the case of the creamer, it
will oxidize (burn) in the presence of a flame and oxygen when
dispersed. This can be a very rapid and potentially dangerous situation.
Thanks for using NEWTON!
---Nathan A. Unterman
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Update: June 2012