Final answer:
Yes, the change in cuvette can introduce a determinate error in the spectrophotometric determination of iron, as differences in cuvettes can affect absorbance readings and impact the resulting calibration curve and analysis.
Step-by-step explanation:
Yes, the change in cuvette can lead to a determinate error in the analysis. A cuvette is an important component in spectrophotometric determination, and cuvettes can have slight differences in the path length or the optical properties of the glass from which they are made. When the analyst prepares a calibration curve and measures the absorbance for a series of standards using one cuvette and then uses a different cuvette for the measurement of the sample, any differences in the cuvettes can cause variations in the absorbance readings. Since spectrophotometry relies on the absorbance of light passing through a solution in a cuvette, any change in the cuvette that affects light transmission, such as a difference in path length or the presence of scratches or impurities, can introduce an error that directly affects the absorbance reading and thus the determination of %w/w Fe in the sample. To mitigate this error, it would be ideal for the analyst to recalibrate using the new cuvette.