(9) Internal Revenue Code means the Internal Revenue Code of 1986 in effect for the federal tax year beginning on January 1, 2007, not including any changes made by federal law after that date, and any regulations adopted under that code applicable to that period.
Absorbance is the negative logarithm of the percent transmittance divided by 100. A spectrophotometer can be set to measure either the percent transmittance or the absorbance of a solution. In lab, you will be using a spectrophotometer called the Spectronic 20 or Spec 20 to measure absorbance.
1 When vaporised, different elements absorb light of specific frequencies. 2  Atomic absorption spectroscopy (AAS) : A technique used to identify the presence and concentration of substances by analysing the spectrum produced when a substance is vaporised and absorbs certain frequencies of light. Atomic absorption spectroscopy (AAS) : A technique used to identify the presence and concentration of substances by analysing the spectrum produced when a substance is vaporised and absorbs certain frequencies of light.