A series of solutions, containing cobalt (II) chloride were prepared with concentrations shown below. Using PhET Simulation find the absorbance values corresponding to each solution at the preset value of wave length 549 \( \mathrm{nm} \), using \( 1 \mathrm{~cm} \) wide cuvette. \begin{tabular}{|l|l|} \hline \multicolumn{1}{|c|}{ Concentration of Co (II), \( \mathbf{~ m M} \)} & \multicolumn{1}{c|}{ Absorbance } \\ \hline \( \mathbf{1 2 1} \) & 0.88 \\ \hline \( \mathbf{9 8 . 0} \) & 0.71 \\ \hline \( \mathbf{6 0 . 0} \) & 0.43 \\ \hline \( \mathbf{2 4 . 0} \) & 0.18 \\ \hline \( \mathbf{1 5 . 0} \) & 0.11 \\ \hline \end{tabular} Plot a calibration line Absorbance versus Concentration. From the graph determine the specific absorptivity.
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This involves plotting the absorbance values on the y-axis against the concentrations of Co (II) in mM on the x-axis. You can use graphing software or graph paper to do this. Make sure to label your axes appropriately. Show more…
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