Two separate aqueous solutions of the same molecular species are analyzed…
CHEMISTRY · Multi-part · AP · Chemistry · Properties of Substances and Mixtures · Properties of Substances and Mixtures
Problem
Two separate aqueous solutions of the same molecular species are analyzed spectrophotometrically at a constant wavelength using identical 1.00 cm cuvettes.
• Solution X has concentration cX and measured absorbance AX.
• Solution Y has concentration cY and measured absorbance AY.
(a) Describe qualitatively how the absorbance of a solution is expected to change as its concentration increases while all other variables are held constant.
(b) Explain, without performing any numerical calculation, why the ratio AXAY is equal to the ratio cXcY for these two solutions.
(c) State one specific experimental condition that must remain unchanged between the measurements of Solution X and Solution Y for the relationship in part (b) to be valid.