When measuring the concentration of the blue dye you get a reading of 3.0 for an initial stock solution, and again after it is diluted. Explain why this result could occur

The beer - lambert law measures the amount of radiation being absorbed when it is passed through the solution.

This formula is as follows -

A = log₁₀ (I₀ / I) = Elc

Where,

E = is abosorption co-efficient

c = Concentration of the solution,

l = Length of the light path

In case of the stock solution, the concentration of blue dye is very high and we see absorbance nearly at 3.0. But when we dilute the solution, the moles of blue dye remains same as before (i. e as in stock solution).

Hence,

The radiation passing through the solution will eventually interact with same number of moles of blue dye in diluted solution and give absorbance nearly 3.0