MODIFICATION OF COLLIN'S METHOD FOR DETERMINING CARBONATE IN SOILS

A rapid method for the estimation of carbonate in soils has been described. Use is made of a solution of trichloroacetic acid (150 g. add in 10 g. water) to liberate the carbon dioxide. The volume of carbon dioxide evolved from pure calcium carbonate is measured. An amount of soil equal to lo divided by the volume of carbon dioxide-evolved from 0.100 g. calcium carbonate is taken for liberating carbon dioxide. The volume of carbon dioxide then evolved divided by 10 gives directly the percentage of calcium carbonate in the soil. The apparatus used is also described and is simple to set up.