Beer–Lambert law
Beer–Lambert law: use molar attenuation coefficient, optical path, concentration. Review the formula, worked example and calculation steps.
Inputs
Use the units shown—
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Formula & explanation
Absorbance = εlc
Variables & units
- Molar attenuation coefficient
- L/(mol·cm) · minimum 0, maximum 1000000000000
- Optical path
- cm · minimum 0, maximum 1000000000000
- Concentration
- mol/L · minimum 0, maximum 1000000000000
Worked example
Use the displayed example inputs, then follow the substituted values in the solution.
Assumptions
Linear absorbance model at the stated wavelength; scattering, stray light and chemical changes can invalidate it.
References
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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