Ocean Optics Overture - Manual (Page 43)

Chapter 5 Applications
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Spectrophotometric analysis of commercial aspirin
Acetyl Salicylic Acid (ASA) complex ion is formed by hydrolyzing the ASA or aspirin sample in NaOH
solution and complexing it with Fe3+ ion in acid solution to bring out the color with a maximum
absorption at a wavelength of 530 nm.
Spectrophotometric determination of an equilibrium
constant
Investigating the reaction between aqueous solutions of iron (III) nitrate, Fe(NO3)3, and potassium
thiocyanate, KSCN. The reaction produces the blood-red complex FeSCN2+. The reaction also
establishes an equilibrium allowing the equilibrium constant to be obtained by sampling multiple
reactions using different concentrations.
Water quality testing using indicator reagents
Phosphate and Nitrate concentrations can be accurately measured by analysis of the absorbance of
solutions using commercial testing reagents.