Using the table of average cmol⁺c kg^-1 clay below, estimate the CEC (cmol⁺c kg^-1 soil) of a soil with 42% clay composed of the following clay minerals: 24% kaolinite, 18% vermiculite, 26% smectite and 10% illite.

Mineral	CEC (cmolc/kg)
Range	Avg
Vermiculite	150 – 200	175
Smectite	80 – 120	100
Illite	20 – 40	30
Kaolinite	5 – 15	10
Organic matter	150 – 500	-----

a.6.3

b.26.4

c.15.7

d. 36.6

e.19.1

Answer rating: 100% (QA)

Clay 42 24 kaolinite 10 1002424 10 illite ... View the full answer