Consider a solution containing 3.78 mM of an analyte, X, and 1.39 mM of a standa
ID: 1011033 • Letter: C
Question
Consider a solution containing 3.78 mM of an analyte, X, and 1.39 mM of a standard, S. Upon chromatographic separation of the solution peak areas for X and S are 4001 and 10867, respectively. Determine the response factor for X relative to S.
a) F = ?
To determine the concentration of X in an unknown solution, 1.00 mL of 8.50 mM S was added to 3.00 mL of the unknown X solution and the mixture was diluted to 10.0 mL. After chromatographic separation, this solution gave peak areas of 6299 and 4703 for X and S, respectively.
b) Determine the concentration of S (in mM) in the 10.0 mL solution.
c) Determine the concentration of X (in mM) in the 10.0 mL solution.
d) Determine the concentration of X (in mM) in the unknown solution.
Explanation / Answer
a) Response factor F = (4001/3.78)/(10867/1.39) = 1058.4656/7817.9856 = 0.1354
b) concentration of S (mM) in 10 ml solution = 8.50 mM x 1 ml/10 ml = 0.85 mM
c) concentration of X in 10 ml solution = 6299/(0.1354 x (4703/0.85)) = 8.41 mM
d) concentration of X (mM) in unknown solution = 8.41 mM x 10 ml/3 ml = 28.03 mM