The cation exchange capacity of a mineral soil containing pre-dominately kaolinitic clay minerals generally ranges between

The cation exchange capacity of a mineral soil containing pre-dominantly kaolinitic clay minerals generally ranges between 3 - 15 meq per 100 gm soil.
Cation exchange capacity is the amount of a cation that can be exchanged by another cation on the surface of a clay mineral. It is expressed in cmol (+) per kg which is numerical to meq per 100g, where mol (+) represents moles of electrical charge.