Question

If dye x has a molar absorptivity, ε = 4.50 x 104 cm-1 m-1, at a certain wavelength, what concentration of the dye, in a 1.00 cm cuvette cell will produce an absorbance of 0.417?

Answer 1

For this problem, the working equation should be used from the Beer's Law:

A = ∈lc,
where
A is the absorbance
∈ is the molar absorptivity
l is the length of path of the cuvette diameter
C is the concentration of the sample placed inside the cuvette

Substituting the values:

0.417 = (4.50×10⁴ cm⁻¹ M⁻¹)(1 cm)(C)
Solving for C:
C = 9.27×10⁻⁶ M