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Beer's Law Application

APCHEM-V8LJMX

Beer's Law states that $A = abc$, where $A$ is absorbance, $a$ is the molar absorptivity constant, $b$ is the path length, and $c$ is the molar concentration.

Which of the following would be an INCORRECT application of Beer's Law?

A

The path length is irrelevant, as long as it is inversely proportional to the molar concentration when determining the concentration of an unknown as compared to a standard curve.

B

The molar concentration is directly related to absorption of light by the sample and is used to develop a standard curve.

C

The concentration of an unknown sample can be easily determined from a standard curve of known concentrations plotted against absorbance for a fixed path length.

D

The use of Beer's Law and a spectrophotometer for a colored sample is a better method of determining molar concentration than visual comparison.