There are several problems. First, the concentration of arsenic in your sample is too high to be measured. This is obvious from two observations. First, the double peak, which is actually a single peak with a Zeeman absorbance reversal in the center, indicates that you are beyond the concentration at which the Zeeman background correction method results in a negative slope of the calibration line. The second indication that the concentration is too high, is that the arsenic absorbance never returns to baseline until after the atomization step (5 seconds) is completed.

What steps do you take to resolve this problem?

Click here to see the correct answer.