Typical spectrophotometric measurements are made with cell lengths of 1.00 cm. However, some special cells are designed much longer. There are two common reasons for doing this. One is because it may not be possible, due to solubility limitations, to create solutions with high enough concentration to absorb measurable amounts of light.

5. True or False. If the molar absorptivity () of an analyte is very low, or if the concentration is low such as with a gas, a longer light path could produce enough change in absorbance to be used in an analysis. (2 points)

6. Beer's law allows the use of light absorption or emission to make quantitative observations. For example, a solution of the drug tetracycline showed a percent transmittance of 39.6% at a wavelength of 254 nm. What is the absorbance of the solution? (3 points)