Answer:
For the control experiment: [tex]0.0552 M[/tex] of aqueous solution of erioglaucine has absorbance of [tex]0.035 M\\[/tex]
From Lambert-Beer's law we know:
[tex]Absorbance = e\cdot c \cdot l\\[/tex]
Here; e is the molar absorptivity coefficient of erioglaucine
l = length of cuvette in which the solution is taken = [tex]1 cm[/tex]
A sorbance by the erioglaucine = total absorbance - absorbance by distilled [tex]water = 0.331-0.019 = 0.312[/tex]
So; by putting the values in the above equation; we get:
[tex]0.312 = 0.0552 M \cdot e\cdot~1cm\\[/tex]
So; [tex]e = \frac{0.331}{0.0552} M^{-1}cm^{-1}= 5.65 M^{-1}cm^{-1}[/tex]
The molar absorptivity coefficient of erioglaucine is [tex]5.65 M^{-1}cm^{-1}\\[/tex]
The absorbance of erioglaucine in distilled water (contaminated with metal ions) is: [tex]0 .217[/tex]
The absorbance of distilled water is [tex]0.019[/tex]
So; absorbance of erioglaucine itself is : [tex]0.217-0.019 = 0.198[/tex]
Again using Lambert Beer law; we get:
[tex]A= e\cdot c\cdot l[/tex]
[tex]0.198 = 5.65 M^{-1}cm^{-1} \cdot c \cdot 1 cm[/tex] [tex]( c = concentrartion)[/tex]
c = 0.198/5.65 M = 0.035 M
The concentration of the erioglaucine is [tex]0.035 M\\[/tex]
Explanation:
