Consider the following statements. Cation exchange of soil colloidal clay is due to
1. Silicon tetrahedral layer
2. Isomorphous substitution
3. Hydration of clays
4. Broken edges of clay lattices
The correct sequence is

Cation exchange in the soil is the capacity of the particles to attract and absorb cations (positively charged ions).
Cation exchange of soil colloidal clay is due to isomorphous substitution and broken edges of clay lattices. Isomorphous substitution in a clay mineral is the process of replacing one structural cation for another of similar size.