SOLVED: state when standard addition and internal standard calibration, instead of calibration curve, is desirable, and why.

An investigator employed a single standard addition method to d... | Filo

SOLVED: Multiple standard addition method was used for determining Fe in a natural water sample. Ten-milliliter aliquots of the sample were pipetted into 50.00-ml volumetric flasks. Exactly 0.00, 10.00, 15.00, and 20.00 ml of a standard solution containing 11.1 ppm of Fe3 were added to each flask, followed by an excess of thiocyanate ion to give the red complex Fe(SCN)2 . After dilution to volume, the absorbance of the five solutions was measured in a 982-cm cell at 480 nm and found to be 0.240