ABSORBANCE (noun)

 

The amount of light absorbed by a liquid sample in colorimetric analysis. The initial amount of light (I₀) shining through a liquid sample will decrease as it passes through the sample because it is absorbed by the chemicals within. The amount of light that re-emerges (I) will be less than I₀. Mathematically, absorbance (A) = log (I₀/I); no units. Using Beer's Law, absorbance = lc.