Question

Cation exchange capacity (CEC) is an important soil property and its magnitude is determined by the nature of the colloids present.

(i) Describe the type of soil colloid(s) that have permanent charge and explain why the charge is permanent.

(ii) Describe the type of soil colloid(s) that have variable charge and the structures that lead to this variability.

(iii) What environmental factor(s) are responsible for changing soil colloid charge and how does it (do they) elicit its (their) effect.

Answer 1

I