Absorbance is a measure of the amount of light that is absorbed by a sample. It is denoted by the symbol ‘A’ and is defined as the negative logarithm of the ratio of the intensity of incident light to the intensity of transmitted light through the sample.
Mathematically, absorbance can be expressed as:
A = -log(I/I<sub>0</sub>)
where I is the intensity of transmitted light and I<sub>0</sub> is the intensity of incident light.
Absorbance is commonly used in chemistry and biochemistry to determine the concentration of a substance in a solution. This is done by measuring the absorbance of the solution at a particular wavelength and comparing it to a standard curve.
The relationship between absorbance and concentration is described by the Beer-Lambert law, which states that the absorbance of a sample is directly proportional to the concentration of the absorbing species and the path length of the sample.
In summary, absorbance is a useful tool for quantifying the amount of light that is absorbed by a sample and can be used to determine the concentration of a substance in a solution.
