In
chemistry, the path length is defined as the distance that light (
UV/
VIS) travels through a sample in an analytical cell. Typically, a sample cell is made of
quartz, glass, or a plastic rhombic
cuvette with a volume typically ranging from 0.1 mL to 10 mL or larger used in a
spectrophotometer. For the purposes of spectrophotometry (i.e. when making calculations using the
Beer-Lambert law) the path length is measured in centimeters (rather than in meters).
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