CHEM123L Lecture 2: Bio-Lab-2-Spectroscopy
Document Summary
In this lab the purpose was to examine the absorbance of substances using spectroscopy. This technique would be used to examine the absorbance levels of a solution of fast green and different chloroplast pigments. Spectroscopy works by isolating a particular wavelength and focusing it on the substance while inside the spectrophotometer. The substance can transmit the beam and from there, the spectrophotometer can determine how much of the beam was transmitted using an absorbance scale (jones, reed, & weyers, 2007). The wavelength with the highest absorbance is then used to plot an absorbance vs. concentration graph. According to beer"s law, the concentration of a certain substance is directly proportional to the absorbance at a given wavelength. But its use as a food dye is becoming phased out because it can cause disease and mutations. It has other uses as well such as a stain for gel electrophoresis.