273,445 views
29 votes
29 votes
In the process of performing a spectrophotometric determination of iron, an analyst prepares a calibration curve using a single-beam spectrophotometer. After preparing the calibration curve, the analyst drops and breaks the cuvette. The analyst acquires a new cuvette, measures the absorbance of the sample, and determines the %w/w Fe in the sample. Does the change in cuvette lead to a determinate error in the analysis

User Nakor
by
2.3k points

2 Answers

13 votes
13 votes

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.

User Librik
by
3.2k points
15 votes
15 votes

Answer:

Yes.

Step-by-step explanation:

Yes, the change in cuvette lead to a determinate error in the analysis if the different cuvette is used for the analysis because the amount of liquid sample that is used has different volume. If both cuvette are of the same type and has no difference in their structure and size then there is error occurs in the analysis but if both cuvette are different from one another then the error will occur in the analysis. because the amount of liquid that is used has different volume.

User Petrba
by
2.7k points