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The molar absorptivity of Beta-carotene at 490 nm is 1.36 x 105 M-1cm-1. What is the concentration of a solution of Beta-carotene that has an absorbance, A490 = 140 in a cell with a path length of 1 cm? The molar absorptivity of Beta-carotene at 490 nm is 1.36 x 105 M-1cm-1. What is the concentration of a solution of Beta-carotene that has an absorbance, A490 = 140 in a cell with a path length of 1 cm? 2.5 x 10-4 M 5.0 x 10-4 M 1.3 x 10-4 M 2.0 x 10-3 M 1.0 x 10-3 M?

User Timothyjc
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Answer:

The correct answer to the following question will be Option E (1.0 x 10⁻³ M).

Step-by-step explanation:

The given values are:


A\lambda =140


\varepsilon=1.36* 10^5 \ M \ {cm^(-1)}

L = 1 \ cm

As we know,


A\lambda=\varepsilon CL

On putting the given values in the above formula, we get


140=1.36* 10^5* C* 1


C=(140)/(1.36* 10^5)


C=102.9* 10^(-5) \ M

So that option E is the right answer.

User GemK
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