Solubility of a mineral as function of pH
External Script File "ReactionDefinition.in"
USE solution 1
Fix_H+ -@pHIterator NaOH 10
-force_equality true
O2(g) -0.677
Fe(OH)3(a) 0 0
Input
Fix_H+; H+ = H+; log_k 0
GLOBAL_VARIABLE pHStart 2
GLOBAL_VARIABLE pHEnd 12
GLOBAL_VARIABLE pHSteps 100
COUNTER pHIterator @pHStart
COUNTERINCR pHIterator = (@pHEnd-@pHStart)/@pHSteps
REPEAT include "ReactionDefinition.in" "solubility.in" @pHSteps
Selected_output 1000
-file Fe(OH)3 solubility.out
-pH true
user_punch 1000
-headings logFe
-start
10 punch log10(TOT("Fe"))
-end
selected_graph 1000
-fig_nr 1
-fig_x pH
-fig_y logFe < vk false ls 1 >
-fig_xt "pH"
-fig_yt "log_{10} Fe_T (mol/kgw)"
-fig_group "Custom"
-fig_variabletype "Solubility"
-fig_name "Fe3(OH)a"
-start
set xrange [2:12]
set yrange [-8:0]
set ytics 2
set title "Solubility of Fe(OH)_3"
set style line 1 linetype 1 lc "blue" lw 3
-end
SOLUTION 1
pH 1.8
units mol/kgw
Fe(3) 1e-1
Na 1e-1
F 1e-1
include$ solubility.in