Re: What happpens to the combusted Argon gas from an ICP spectrometer?

Michael,

The plasma of an Inductively Coupled Plasma (ICP) is comprised of a 
significant concentration of both Argon cations (Ar+) and electrons such 
that the net charge in the plasma is zero.  Once the plasma ionization is 
initiated (usually from a spark from a Tesla coil), the radio frequency 
generator provides the energy to maintain the ionization.  The argon plasma 
can reach temperatures of more than 10,000 K but the heat produced is not 
the result of combustion or chemical reaction.  Instead, the high powered 
radio frequency supplies energy to the ions and electrons within the coil. 
Argon atoms are normally deemed as inert which means that they are very 
stable in their uncharged state.  In order to keep the cations and 
electrons apart, the Rf generator is tuned to a frequency which the plasma 
can absorb and will keep the atoms ionized.  The absorbed Rf energy is 
converted by the plasma and in turn released as heat.  Using this principle 
the temperature of the plasma can be varied by increasing or decreasing the 
power of the radio frequency.  As a result, the optimum plasma temperature 
can be used depending on the type of analysis being carried out.

Upon exiting the radio frequency coil, the ions and electrons no longer 
have the energy from the coil to remain separate and recombine into argon 
atoms.

I hope this answers your question.

							John.