Computing Ion Balance

RockWorks | Utilities | HydroChem | Ion Balance

This program reads a listing of ion concentrations from the datasheet and computes cation:anion ratio for each sample, in milli-equivalents per liter. The computations are stored in a column in the datasheet.

RockWorks uses the following equation for the ion balance:

( ( cations - anions ) / ( cations + anions ) ) x 100

Menu Options
Step-by-Step Summary

Menu Options

• Input Columns: The prompts along the left side of the window tell RockWorks which columns in the input datasheet contain what data.
  Click on an existing name to select a different name from the drop-down list. (More about the input data.) 
  
  • Sample ID: If you have sample numbers listed for your sites, choose the column where these are listed.
  • Symbol: Choose the column that lists specific symbols for the individual samples.
  • Na, K, Ca, Mg: Choose the columns that list these required cations. The measurements must be listed in ppm or mg/l units.
  • Cl, HCO3, CO3, SO4: Choose the columns that list these required anions. The measurements must be listed in ppm or mg/l units.
  • Cation A, B, C, D: If you are including any additional cations (see Additional Cations, below), choose their columns here.
  • Anion A, B, C, D: If you are including any additional anions (see Additional Anions, below), choose their columns here.
    
    
• Output Column: This prompt tells RockWorks where to store the computed values.
  • Ion Balance: Select the name of the column in the current datasheet into which the computed ion balance for each sample is to be stored. 
    ! Any existing data in the selected column will be overwritten.
    
    
• Additional Cations: Expand this heading, in the right side of the window, to turn on/off the inclusion of any additional cations (you can list 4 each) in the ion balance and to specify their conversion factors.  
  • Insert a check in the additional ions to be included.  The program will read "Cation A" data from the input column to the left specified for "Cation A,"  "Cation B" data from the column specified for "Cation B" and so on.
  • Conversion Factor:  For each cation, you must enter the real number value to be used to convert the measurements in parts per million to milli-equivalents.  (More on conversion factors.)
    ! This is important - RockWorks will not know this conversion factor automatically. You need to enter it manually.
    
    
• Additional Anions:  Expand this heading to turn on/off the inclusion of any additional anions in the ion balance and to specify their conversion factors.  You can specify up to 4 additional anions.
  • Insert a check in the additional ions to be included.  The program will read "Anion A" data from the input column to the left specified for "Anion A,"  "Anion B" data from the column specified for "Anion B" and so on.
  • Conversion Factor:  For each anion, you must enter the real number value to be used to convert the measurements in parts per million to milli-equivalents.  (More on conversion factors.)
    ! This is important - as mentioned above, RockWorks will not know this conversion factor automatically. You need to enter it manually.
    
    

Step-by-Step Summary

1. Access the RockWorks Utilities program tab.
2. Create a new datasheet and enter/import your hydrochemistry data into the datasheet.
   Or, open one of the sample files and replace that data with your own. (In the Samples folder, an example file = "RockWorks17 Data\ Samples\Hydrochemistry_01.rwDat".)
3. Select the HydroChem | Ion Balance menu option.
4. Enter the requested menu settings, described above.
5. Click the Process button to continue.

The program will read the concentrations of all declared ions (standard and additional), convert them to milli-equivalents per liter using the declared conversion factors, and compute the ion balance. The values will be recorded in the selected column in the datasheet.

Back to Hydrochemistry Menu Summary

RockWare home page