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bioNRICH is the area of the stemNRICH site devoted to the mathematics underlying the study of the biological sciences, designed to help develop the mathematics required to get the most from your study of biology at A-level and university.

Light Absorbance

Stage: 5 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3


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The molar extinction coefficient $\epsilon(\lambda)$ of a chemical measures theintrinsic property of how the chemical absorbs light of wavelength $\lambda$. When such light passes through a homogeneous solution of the chemical, the absorbance $A$ is measured by the Beer-Lambert law $A=\epsilon(\lambda) cL$, where $c$ is the concentration of the chemical and $L$ is the path length of the light passing through the solution. Recall that 1 katal = 1 mole per second.
With thanks to Keith Johnstone for providing the template for this question.