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Potassium dichromate and potassium permanganate have over lapping absorption spectra in 1mol·L-1 H2S

Potassium dichromate and potassium permanganate have over lapping absorption spectra in 1mol·L-1H2SO4. K2Cr2O7has an absorption maximum at 440nm,and KMnO4has a band at 545nm. A mixture is analyzed by measuring the absorbance at these two wavelengths with the following result:A440=0.405,A545=0.712 in a 1.00cm cell(approximate;exact length not known). The absorbances of pure solution of K2Cr2O7(1.00×10-3mol·L-1)and KMnO4(2.00×10-4mol·L-1)in 1mol·L-1H2SO4,using the same cell gave the following resuits;

ACr,440=0.374,ACr,545=0.009,AMn,440=0.019,AMn,545=0.475. Calculate the concentrations of dichromate and permanganate in the sample solution.

提问人:网友anonymity 发布时间:2022-01-07
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