Appendix XI P. Dry Residue of Extracts

In a flat-bottomed dish about 50 mm in diameter and about 30 mm in height, introduce rapidly 2.00 g or 2.0 mL of the extract to be examined. Evaporate to dryness on a water-bath and dry in an oven at 100-105 °C for 3 h. Allow to cool in a desiccator over diphosphorus pentoxide R or anhydrous silica gel R and weigh. Calculate the result as a mass percentage or in grams per litre.