a)why do chemist prefer to read/ record the absorbance, rather that the percent transmittance, of light when analyzing a sample having a visible color?

b) three parameters affect the absorbance of a sample. Which one is the focus of this experiment?

a) The log of AbsorbTance, which is called absorptivity, is proportional to concentration.

b) What experiment?

B) the concentration of the absorbing substance

a) Chemists prefer to read/record the absorbance, rather than the percent transmittance, of light when analyzing a sample with visible color because absorbance is a more linear and quantitative measure of light absorption. The absorbance value is directly proportional to the concentration of the absorbing species in the solution, as stated by the Beer-Lambert Law. This allows chemists to accurately determine the concentration of the substance being analyzed by measuring its absorbance. In contrast, percent transmittance is inversely related to absorbance, and the relationship is not as straightforward. Also, the percent transmittance values tend to saturate at higher concentrations, making it difficult to accurately determine the concentration using this parameter.

b) The focus of this experiment is not explicitly stated, but the three parameters that generally affect the absorbance of a sample are the concentration of the absorbing species, the path length that the light passes through in the sample, and the molar absorptivity (or extinction coefficient) of the absorbing species. Depending on the specific experiment, one of these parameters may be the principal focus.

a) Chemists prefer to read/record the absorbance rather than the percent transmittance of light when analyzing a sample having a visible color because absorbance is a more sensitive and accurate measure of the concentration of a substance in the sample. The absorbance is directly proportional to the concentration of the substance, according to Beer’s Law. In contrast, percent transmittance is inversely proportional to the concentration. When a substance has a visible color, it means it absorbs light in the visible spectrum, and the intensity of this absorption can be quantified by measuring the absorbance. This allows chemists to accurately determine the concentration of the substance in the sample.

b) The three parameters that affect the absorbance of a sample are the concentration of the substance, the path length of the sample cell, and the molar absorptivity (ε) of the substance. In this experiment, the focus is on determining the concentration of the substance. By measuring the absorbance and using the known path length and molar absorptivity of the substance, chemists can calculate the concentration of the substance in the sample.