A solution containing3.47mMX(analyte) and1.72mMS(standard) gave peak areas of3473and 10222,respectively, in a chromatographic analysis. Then1.00mLof 8.47mMSwas added to5.00mLof unknownX,and the mixture was diluted to10.00mL. This solution gave peak areas of5428and4431forXandS, respectively.

(a) Calculate the response factor for the analyte.

(b) Find the concentration of S(mM)inthe10.0-mLmixture.

(c) Find the concentration of X(mM)inthe10.0-mLmixture.

(d) Find the concentration ofXintheorignalunknown.

Short Answer

Expert verified

(a) The response factor for the analyte is 0.1684

(b) The concentration ofSmMis0.847mM

(c) The concentration of XmMis6.16mM

(d) The concentration of Xin the original unknown is12.32mM

Step by step solution

01

Definition of the equestion 

In this task, we have a solution that contains3.47mM×analyteand1.72mMS(standard)and yields chromatographic peak areas of 3473and10222.1mLof 8.47mMSwas mixed with 5mLof Xrunknown and diluted to $ 10mL, yielding peak areas of 5428and 4431for XandS,respectively.

02

Step 2:

(a)

The:#c34632''>responsefactoreresponsefactorfortheanalytewillbecalculatedhere.AxX=FASS3.4733.47mM=F102221.72mMF=0.1684Theresponsefactorfortheanalyteis0.1684

03

The concentration of S(mM) in 10mL the mixture

(b)

TheconcentrationofSmMinthe10mLmixtureis:S=8.47mM×1mL10mL=0.847mMTheconcentrationofSmMis0.847mM

04

The concentration of X(mM) in the 10mL mixture

(c)

TheconcentrationofXmMinthe10mLmixtureis:

AxX=FAS[S]5428[X]=0.168444310.847mM[X]=6.16mMTheconcentrationofX(mM)is6.16mM

05

Concentration of in the original unknown

(d)Theconcentrationofxintheoriginalunknownis:Theoriginalconcentration=2×dilutedconcentration=2.6.16mM=12.32mMTheconcentrationofxintheoriginalunknownis12.32mM

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