【Daily Question】Chemical Analysis Version, 2020.6.10
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This post was last edited by zjp on 2020-6-10 08:36. Multiple-choice question: There are two solutions of the same colored substance with different concentrations, namely Solution A and Solution B. Using cuvettes of the same thickness and measuring at the same wavelength, the absorbance values obtained are: A_A = 0.20； A B =0.30. If the concentration of A is 4.0×10-4 mol/L, then the concentration of B is ( ). A、8.0×10-4 mol/L B、6.0×10-4 mol/L C、1.0×10-4 mol/L C
B, according to Beer’s law A=Kbc: for substance A, 0.2=Kb*4.0×10-4 mol/L; for substance B, 0.3=Kbc_B. It was determined that c B = 6.0×10-4 mol/L
C, 1.0×10-4 mol/L