2. a. Choose a solution and keep concentration and path length constant as you graph the absorbance for different wavelengths. Solution: Absorbance 380 580 Wavelength (nm) 780 (nm) Abs b. What is the value for the "preset" wavelength for your solution? Mark this point on your graph. c. Why do you think the "preset" wavelength is the best wavelength to use for this solution? 3. Would you use the same wavelength of light to do spectroscopy experiments with different colored solutions? Why or why not? 4. In a lab experiment monitoring the change in concentration of a red-brown substance, FeNCS2+, what would be an appropriate monitoring wavelength? Explain your answer using your conclusions about beam color, solution color, and absorbance above