This paper describes the use of Solver function, contained in the Microsoft Excel spreadsheet
package, in computing the chemical equilibrium of known substances in either an ideal or non-ideal
gas phase by the method of direct Gibbs energy minimization. Apart from some deficiency of Solver
in applying the generalized reduced gradient method for this type of problem, the approach is simple
to understand and apply and provides a direct solution procedure whereas the traditional approach
often employs a high-level programming language. The results are compared with those obtained by
a Fortran program, and found to be in satisfactory agreement