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Beer–Lambert law


A student is tasked with determining the number of moles of KMnOA4(aq) in a 150.mL sample of an unknown solution. The student prepares a series of solutions with known concentrations of KMnOA4(aq) and measures the absorbance of each at an appropriate wavelength. These data are used to construct the calibration plot shown below.
A graph shows the absorbance of solutions of potassium permanganate at different concentrations. The X-axis represents the concentration with the unit of a mole per liter with an interval from zero to 4 times 10 to the power of negative 4, and a scale of 2 times 10 to the power of negative 4 per two lines. The Y-axis represents the absorbance with an interval from zero to 1 and a scale of 0.2 for every two lines. The graphical representation shows a diagonal line showing as the concentration increases, the absorbency of light increases. The line graph has 5 points of data to represent this relationship.
If the absorbance of the unknown solution is 0.50, how many moles of KMnOA4(aq) does the 150.mL sample contain?
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