Lecture 3311/28/05

1 seminar left Urban sprawlToday at 4

No lab report will be due on Tuesday, November 29 For this week only, you can skip all the data analysis. 

SpectroscopySome interesting applications

Scatchard Plot

To get equilibrium constant

P + X ⇄ PX

Plot ΔA/[X] vs. ΔA

Two cases K small K large

AKPεK]X[

Ao

Job’s PlotMethod of continuous variation

Way to determine the formula of a complex ion

P + X ?????

Plot: Absorbance vs. mole fractionX-axis

Enzyme-Linked Immunosorbent Assay (ELISA)

Time-resolved Fluorescence Immunoassay

Microtox/Deltatox

Chromatography

Extraction

Partition coefficient:1

2

1s

2s

]S[

]S[

A

AK

1Vqm

Vm)q1(

]S[

]S[K 2

1

2

n

21

1n

21

1

KVV

Vq

KVV

Vq

After 1 extraction

After n extractions

Solute A has a partition coefficient of 3 between toluene and water. Which is a more efficient extraction of a 100- mL 0.010 M aqueous solution: One extraction with 500-mL toluene Five extractions each with100-mL toluene

Distribution coefficient

1 in phase entration total conc

2 in phase entration total concD