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simultaneous equations for chemical speciation

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  • Subject: [mg100186] simultaneous equations for chemical speciation
  • From: Jem & Tracy <jemandtracy at>
  • Date: Wed, 27 May 2009 04:09:01 -0400 (EDT)

Hi, I am a postgrad student and completely new to mathematica, I am just 
starting to realise the possibilities.

I am trying to do a chemical speciation calculation.
I have a set of simultaneous equations which represents the equilibria, 
mass balance, and charge balance in the system.

I want to eliminate some of the variables, and then be able to solve for 
the remaining ones.
My system of equations looks like this:

Basically, I can solve for the variable I want, but I am having trouble 
eliminating the ones I don't want (ie. I am getting an answer that is in 
terms of the wrong variables)
Sofar my formula looks like:

Solve[{a == b + c + d, e == f + g + c + 2 d, h == c/(b*g),
  i == d/(c*g), h*i == d/(b*g^2), j == m*g/f, k == l*m,
  n + m + b + c == g + l}, {g}]

If I use a similar formula for the "Eliminate" function, I get error 

I have been in the help files for ages, and don't really understand how 
to do this.
I would really appreciate some pointers!!

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