AP Chemistry / Unit 3: Properties of Substances and Mixtures
3.13 Beer-Lambert Law
Notes
$$A=\varepsilon bc$$
- Absorbance $A$ is proportional to concentration $c$ (for a given path length $b$ and molar absorptivity $\varepsilon$).
- Use a calibration curve and the wavelength of maximum absorbance.
Practice
Doubling the concentration doubles:
$A\propto c$.
Fingerprints on the cuvette would make the measured concentration:
Extra light is blocked.
A calibration curve plots:
A straight line through standards.
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