52. Solution to Chemistry Problem

34(2). From a 20.00 g sample of methylene chloride CH2Cl2, 100.0 ml of a solution in chloroform were prepared to plot a calibration graph. V ml of this solution were added to 50.0 ml measuring flasks and brought to the mark with chloroform. Using the baseline method at 7.98 μm, the values ​​of A = -log*I/Io were found, which are given below:
V, ml 2.00 4.00 6.00 8.00 10.00
A 0.085 0.155 0.225 0.300 0.375
Calculate the concentration (g/l) of methylene chloride in the test solution if after diluting 25.0 ml of it with chloroform to 50.0 ml, the following values ​​were found: A = 0.280