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Beer-Lambert Law:
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The Beer-Lambert Law describes the relationship between the concentration of a solution and its absorbance of light. It states that absorbance is directly proportional to the concentration of the absorbing species and the path length through which light travels.
The calculator uses the Beer-Lambert Law equation:
Where:
Explanation: The equation shows that absorbance increases linearly with both concentration and path length when the molar absorptivity is constant.
Details: Accurate concentration determination is essential in analytical chemistry, pharmaceutical analysis, environmental monitoring, and biochemical research for quantifying unknown sample concentrations.
Tips: Enter absorbance (typically between 0.1-1.0 for best accuracy), molar absorptivity from standard tables or calibration curves, and path length of the cuvette. All values must be positive.
Q1: What Is The Ideal Absorbance Range For Accurate Measurements?
A: The optimal range is 0.1-1.0 absorbance units. Below 0.1, noise dominates; above 1.0, detector saturation and deviations from linearity may occur.
Q2: How Do I Determine Molar Absorptivity?
A: Molar absorptivity is typically determined experimentally by measuring absorbance of solutions with known concentrations and applying the Beer-Lambert Law.
Q3: When Does The Beer-Lambert Law Not Apply?
A: The law may not hold at very high concentrations, with polychromatic light, in scattering solutions, or when chemical associations occur at different concentrations.
Q4: What Is The Typical Path Length Used?
A: Standard cuvettes have 1 cm path length, though other sizes (0.1 cm to 10 cm) are available for different concentration ranges.
Q5: Can This Be Used For Mixtures?
A: For mixtures, absorbance is additive, but multiple wavelengths and matrix algebra are needed to determine individual component concentrations.