When a student measures the absorbance of two aqueous cobalt(II) nitrate solutions…
CHEMISTRY · Single correct · AP · Chemistry · Properties of Substances and Mixtures · Properties of Substances and Mixtures
Problem
When a student measures the absorbance of two aqueous cobalt(II) nitrate solutions using identical 1.00 cm cuvettes at the same wavelength, doubling the concentration of the solution results in an absorbance that is approximately twice as large. Which of the following best explains this observation?
(a) Adding more solute increases the effective path length of light through the solution.
(b) Doubling the concentration doubles the molar absorptivity of the species at the selected wavelength.
(c) Absorbance is directly proportional to concentration when both the path length and the molar absorptivity remain constant.
(d) The spectrophotometer automatically adjusts its baseline upward for more concentrated samples.