Question

a. Calulate the R40 conentration of your unknown sample?

b. Calculate the B1 concentration of your unknown sample?

using the following data

Fraction 1 (Unknwon R 40) @ 505 nm Absorbance is 0.14179

Fraction 2 (Unknown B1) @ 630 nm absorbance is 0.41433

R40 Standard (5ppm) @ 505 nm absorbance is 0.26298

B1 Standard (5ppm) @ 630 nm absorbance is 0.85971

Answer 1

As the absorbance are measured under same wavelength for same compounds we can use Beer's law which states that Absorbance = eLc where c is the concentration and e is the molar extinction coefficient and L is the path length

and we know that we have same wavelength and path length hence

we can use C₁ = (A₁ / A₂) * C₂

Where C1 is the unknown concentration and C2 is the known standard concentration

For R40

C2=5ppm

A2=0.26298

A1=0.14179

HENCE C1=5*(0.14179/0.26298)=2.695 PPM

FOR B1

C2=5ppm

A2=0.85971

A1=0.41433

HENCE C1=5*(0.41433/0.85971)=2.41 PPM

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