A standard solution was put through appropriate dilutions to
give the concentrations of iron shown next. The iron(II)-1,10,phenanthroline
complex was then formed in 25.0-mL aliquots of these solutions, following which
each was diluted to 50.0 mL. The following absorbances (1.00-cm cells) were
recorded at 510 nm:
(a) Plot a calibration curve from these data.
(b) Use the method of least squares to find an equation
relating absorbance and the concentration of iron(II).
(c) Calculate the standard deviation of the slope and