To calculate the concentration of the copper II sulfate solution, we can use the Beer-Lambert Law, which states:A = * c * lWhere:A = absorbance 0.25 = molar absorptivity 5,400 M^-1cm^-1 c = concentration unknown l = path length of the cuvette 1 cm Rearranging the equation to solve for the concentration c :c = A / * l Now, plug in the given values:c = 0.25 / 5,400 M^-1cm^-1 * 1 cm c = 0.25 / 5,400c = 0.0000463 MSo, the concentration of the copper II sulfate solution is approximately 0.0000463 M or 46.3 M.