Spectrophotometry help!? Would measuring the absorbance of the standard solutions used to prepare a calibration curve...
Spectrophotometry help!?
Would measuring the absorbance of the standard solutions used to prepare a calibration curve and the unknown sample using a wavelength 10 nm higher or lower than lambda max provide an accurate concentration value for the unknown? Explain.
If in an experiment, the pathlength of the light is 1 cm, and the concentration unit of the standard solutions is reported as mM, what would the units of the molar extinction coefficient, ε, be?
Homework Answers
1) No, it wouldn't give accurate results. The Absorbance of the Unknown, must be measured at the Wavelength, at which the Absorbance of the Standard Solutions are measured to prepare the Calibration Curve. If the Unknown is measured at a wavelength 10 nm. Higher or lower than the lambda max, the Calibration Curve wouldn't be Applicable to calculate the Concentration of the Unknown. Thus, the Result will be inaccurate.
2) The unit of the Molar Extinction Coefficient, in this case would be mM-1cm-1.
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