Question

A `2.3` x `10^-4` `M` solution has trasmittance of `0.508` when placed in a cell of path length `1` `cm` at wavelength `525` `nm`. Calculate the absorbance if concentration is doubled?

Answer 1

The absorbance should be `1.160`, or thereabouts.

Explanation:

The `"Beer Lambert Law"`, holds that `A=epsilonbC`, where `epsilon="molar absorptivity"`; `b="cell path length"; and c="concentration in mol L"^-1`.

So if we double the concentration, (or double the path length), we should in principle, double the absorbance. In practice, it is never this easy to do and deviations are common. The `"Beer Lambert Law"` only approximately holds at low concentrations, `~=0.1*mol*L^-1` or lower.