Column construction, density gradient

The density was measured at room temperature using a density gradient column constructed from toluene and carbon tetrachloride. The column was prepared according to ASTM-D 1505 Method B. The column was calibrated with glass floats of known density. The accuracy of density measurements was estimated to be 0.001 g/cm Small pieces ( 25 mm ) were placed in the column and allowed to equilibrate before the measurements were taken. 

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