1. Lecture 32 11/21/05 2 seminars left

2. Analysis of a Mixture A =  X b[X] +  Y b[Y] +  Z b[Z] +....

4. Spectra overlap 1. Constant concentration of both analytes 1. Find  of each individual component at different 2.Least squares to find best values of [X] and [Y] 1. A m =  X b[X] +  Y b[Y] 2. A calc =  X b[X] guess +  Y b[Y] guess

7. Spectra not-overlapping A’ =  ’ X b[X] +  ’ Y b[Y] at ’ A’’ =  ’’ X b[X] +  ’’ Y b[Y] at ’’

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10. Example 19-1 Find [X] and [Y] in a solution whose absorbance is 0.233 at 272 nm and 0.200 at 327 nm in a 0.100-cm cell.  (M -1 cm -1 ) (nm) [X][Y] 272164403870 32739906420

11. Isosbestic point: X ⇄ Y ε X(465) = ε Y(465)