H2O + 1.0 mM   (NH4)2Cr2O7
+ 1.0 mM   Al2(SO4)3
+ atmospheric CO2   (pCO2 = 3.408)

pH = 4.15

  (at 25 °C)
Electrical conductivity:   489.9 µS/cm   (info)
Ionic strength:   9.337 mmol/L   (info)
Alkalinity:   0.0 meq/L   (info)
Total hardness:   6.0 meq/L   (info)
Carbonate hardness:   0.0 meq/L   (info)
Redox potential (Eh):   918 mV  



Elements   (in mM)

C(4) DIC 1.34e-02
S S 3.00e+00
S(6) Sulfate 3.00e+00
Al Al 2.00e+00
Amm Ammonium 2.00e+00
Cr Cr 2.00e+00
Cr(3) Cr(3) 5.76e-05
Cr(6) Cr(6) 2.00e+00
O(0) O(0) 8.64e-05

Aqueous Species   (in mM)

H+ 7.66e-02
OH- 1.58e-07
CO2 1.33e-02
HCO3- 9.30e-05
CO3-2 8.32e-11
Al+3 6.79e-01
AlOH+2 6.41e-02
Al(OH)2+ 5.36e-03
Al(OH)3 1.02e-05
Al(OH)4- 3.04e-07
AlSO4+ 1.21e+00
Al(SO4)2- 4.31e-02
AlHSO4+2 1.02e-05
NH4+ 1.97e+00
NH3 1.45e-05
NH4SO4- 2.86e-02
HSO4- 8.48e-03
SO4-2 1.67e+00
CrO4-2 1.04e-02
HCrO4- 1.73e+00
H2CrO4 1.52e-05
Cr+3 2.63e-05
Cr(OH)+2 2.27e-05
Cr(OH)2+ 5.76e-07
Cr(OH)3 5.50e-10
Cr(OH)4- 8.29e-17
Cr2O7-2 1.27e-01
CrO2- 2.11e-16
CrSO4+ 2.94e-07
CrOHSO4 7.74e-06
O2 4.32e-05

Minerals   (Ksp values)

Mineral Formula SI Saturation state
Al(OH)3(a) Al(OH)3 -1.85 under-saturated
Cr(OH)2 Cr(OH)2 -32.68 under-saturated
Cr(OH)3(A) Cr(OH)3 -4.38 under-saturated
Cr(OH)3(C) Cr(OH)3 -6.83 under-saturated
Diaspore AlOOH 2.07 super-saturated
Boehmite AlOOH 0.37 super-saturated
Gibbsite Al(OH)3 0.84 super-saturated
Jurbanite AlOHSO4 0.92 super-saturated
Amm2CrO4 (NH4)2CrO4 -11.06 under-saturated
Sulfur S -93.52 under-saturated
AlMetal Al -135.44 under-saturated

Disclaimer:   The pH calculator has been tested with great care. Nevertheless, the results are provided without warranty.