Gcarlen@aol.com wrote:
> 
> The question came up a couple of weeks ago about what kind of gasses are
> given off when a VW aluminum/magnesium engine burns.  I said I would check my
> resources at my firestation and get back to the list.  Well, I finally got
> the answer.
> 
> The main properties that are burning, Aluminum and Magnesium, give off mainly
> Hydrogen and Nitrogen (I'll get back to how Hydrogen affects things later).
>  They also give off particles of Aluminum and Magnesium in a microscopic size
> (which can be lethal in itself if inhaled).  

Magnesium will burn meaning it reacts with oxygen in air if sufficiently
hot.  Once started it is a very exothermic reaction producing magnesium
oxide as the combustion product.  It does not produce hydrogen or
nitrogen.  There is no hydrogen involved in this reaction.  It is
possible for nitrogen oxides to form at these temperatures but the
levels would be minor.  

A mixture of finely divided iron and magnesium will burn producing
molten iron and this reaction was once used as a welding method.  The
oxygen reacts with the magnesium rather than the iron but the heat melts
the iron.  At these temperatures iron oxide (rust) is not formed. 

Larry