3.1: Pre-lab assignment
- Page ID
- 450916
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Please read this entire module on ultraviolet-visible (UV-Vis) absorption spectroscopy. This module should take less than one lab period. It is part of a two-part series with the theme of caffeine analysis in beverages. First, in this module, you will create a serial dilution of caffeine and characterize the solutions using UV-vis. Store your solutions in sealed vials for use in the next module. You have three objectives:
- Create a series of caffeine solutions for use in this and the next module.
- Determine the wavelength of maximum absorbance for each solution.
- Validate the serial dilution using a control.
Written Pre-lab Assignment
Complete the following in your lab notebook and be prepared to discuss these points with your TA.
- In writing, please explain the advantages to using multi-point calibration compared to single-point calibration.
- Describe how you should choose appropriate wavelengths in the following scenarios:
- to quantitate a single component in solution.
- to quantitate two or more components in a solution.
- Prepare a procedure for creation of the caffeine standard solutions described in this module.
- Prepare a table in your notebook to record absorbance data.