What is the unit of EXCHANGE in Cation exchange model?

[Jeonghwan Hwang]

Hi, This is Jeonghwan Hwang
I am studying about Cation exchange model with PHREEQC.
I wandered about the unit of cation exchange model,

Like this example, in "https://wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc/html/final-80.html"
The EXCHANGE part was written as below;

EXCHANGE 1-40
        equilibrate 1
        X                0.0011

and the commentary was written as below;

The amount and composition of the exchanger in each of the 40 cells is defined by the EXCHANGE 1-40 data block. The number of exchange sites in each cell is 1.1 mmol, and the initial composition of the exchanger is calculated such that it is in equilibrium with solution 1.

For this information, I think that the unit of EXCHANGE is "mol", not concentration "mol/L".
Is it right? If not, how can i know the unit data in PHREEQC?

Thank you for kind help,

Sincerely,

Jeonghwan Hwang

[dlparkhurst]

You are right; the unit is moles. You could always check the manual.