Download presentation
Presentation is loading. Please wait.
Published byAntonia Manning Modified over 9 years ago
1
Determination of the Equilibrium Constant
2
Theory Beer’s Law: Concentration is proportional to Absorbance The reaction: Fe +3 + SCN - [Fe(SCN)] +2 Kc = Beer’s Law: Concentration is proportional to Absorbance The reaction: Fe +3 + SCN - [Fe(SCN)] +2 K c =
3
Fe(SCN) +2 absorbs light in the blue-green region –Set up standard curve with absorbance readings for solutions of known concentration –Beer’s Law plot
4
Math Determine moles of each reactant species Determine M for each based on total volume of solution ICE K eq = Lab,P. 298
5
Spectrophotometer 3 clean cuvettes, wipes Empty chamber –Light source on –Power knob: 0%T Water blank –447 nm –Clean cuvette with distilled water –Light source on –T knob: 100% T
6
HNO 3 blank –Set absorbance = to 0 Test solutions Zero the machine frequently http://www.chm.davidson.edu/java/spec/spec.ht mlhttp://www.chm.davidson.edu/java/spec/spec.ht ml
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.