The magnesium in a series of soil samples was characterized byatomic absorption spectrometry (AAS). The instrument was calibratedwith a series of standards: 0, 50.00, 100.00, 250.00 mg/LMgSO47H2O. These samples produced average instrument readings of0.005; 0.192 ; 0.401 ; and 0.993. Triplicate analysis of an unknownyielded instrument readings of 0.328, 0.340, 0.335. What is theaverage concentration and standard deviation of the unknown? Reportyour answer as ppm Mg. THE OPTION IS NOT 211
