ex4 {phreeqc} | R Documentation

## Example 4–Evaporation and Homogeneous Redox Reactions

### Description

Evaporation is accomplished by removing water from the chemical system. Water can be removed by several methods: (1) water can be specified as an irreversible reactant with a negative reaction coefficient in the REACTION keyword input, (2) the solution can be mixed with pure water which is given a negative mixing fraction in MIX, or (3) "H2O" can be specified as the alternative reaction in EQUILIBRIUM_PHASES keyword input, in which case water is removed or added to the aqueous phase to attain equilibrium with a specified phase. This example uses the first method; the REACTION data block is used to simulate concentration of rainwater by approximately 20-fold by removing 95 percent of the water. The resulting solution contains only about 0.05 kg of water. In a subsequent simulation, the MIX keyword is used to generate a solution that has the same concentrations as the evaporated solution, but has a total mass of water of approximately 1 kg. The example can be run using the `phrRunString` routine.

### Source

http://wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc

### References

http://pubs.usgs.gov/tm/06/a43/pdf/tm6-A43.pdf

### See Also

Other Examples: `ex10`, `ex11`, `ex12`, `ex13a`, `ex14`, `ex15`, `ex16`, `ex17`, `ex18`, `ex19`, `ex1`, `ex20a`, `ex21`, `ex22`, `ex2`, `ex3`, `ex5`, `ex6`, `ex7`, `ex8`, `ex9`

### Examples

    phrLoadDatabaseString(phreeqc.dat)
    phrSetOutputStringsOn(TRUE)
    phrRunString(ex4)
    phrGetOutputStrings()

[Package phreeqc version 3.4.10 Index]