Speciation Calculation and Charge Balance
Example Water
Given is the following water:1
| cations | mmol/L | anions | mmol/L | |
|---|---|---|---|---|
| Na | 0.957 | NO3 | 1.100 | |
| K | 0.072 | Cl | 1.805 | |
| Ca | 3.818 | SO4 | 1.520 | |
| Mg | 0.864 | KS43 | 4.960 | |
| Fe(2) | 0.052 | |||
| Mn | 0.019 |
This solution belongs to the example waters of aqion: click on button Open and select ib.sol.
(Alternatively, you can enter it directly into the program, where the KS43 value is to be entered as “Alkalinity” — see right screenshot.)
As no pH and temperature data are available, we use the standard values: pH = 7 and T = 25.
Click on Start to run the calculation.
Results
CBE. The first window summarizes the ion balance (see here):
| charge balance error (CBE): | -1.89 % |
| sum of cations: | 9.59 meq/L |
| sum of anions: | 9.96 meq/L |
Speciation. Click on button next ≫ (two times) to come to the output tables.
Then click on the upper menu button Ions to get the complete speciation (which is a rather long table) — the upper part of this table is shown on the right.
Footnotes
-
taken from “German standard methods for the examination of water, Part 62: Plausibility check of analytical data by performing an ion balance”: DIN 38402-62:2013-10 ↩