You will be required to answer two of the following three questions during the mid-term on October 11th

1) Describe the procedure (both laboratory and texture triangle) you would use to physically classify a soil based on the relative percentages of three different soil separates.

2) Kaolinite and montmorillonite represent two types of crystalline silicate clays that behave as soil colloids. Contrast these two clay colloids in terms of their genesis, micelle structure, charge development and general efficiency in terms of cation/anion exchange capacity.

3) Explain the pH-dependency of colloid (both clay and humus) cation exchange capacity (CEC).