In the Fluorometric analysis of Quinine in Tonic Water Lab Pipette 50 L of the t
ID: 929296 • Letter: I
Question
In the Fluorometric analysis of Quinine in Tonic Water Lab
Pipette 50 L of the tonic water into the 10 mL flask and dilute to 10.00 mL with 0.05 M H2SO4. This will be your first sample for analysis. Prepare a second sample by diluting the first solution by a factor of 2. You can do this by pipetting 1.00 mL of solution the first solution and 1.00 mL of 0.05 M H2SO4 into a vial.
From the platereader (fluorescence spectrophotometry):
From the calibration curve of standards of 0.15, 0.30, 0.45 ppm (quinine standards (10 ppm) ).
R² = 0.98804
y = 495.11x + 180.33
Calculate the concentration of the quinine in the tonic water as determined by the two sample dilutions. Propagate the error in these results. Determine whether there is a significant difference in the results at 95% confidence.
Tonic water sample Tonic water sample (diluted ½) Mean Intensity 375.26 260.73 concentration (ppm) 0.329 0.202Explanation / Answer
calculation for the concentration of quinine :
C1V1 = C2V2
For the first sample 0.05 M x 10 ml = C2 x 50 x 10-3 ml
C2 = 0.05 M
for the second sample 0.05 M x 1ml = C2 x 1 ml
C2 = 0.05M
Now, find out LOD (limit of detection) = 3* standard deviation
For concentartion, consider As given :
y = 495.11 x + 180.33
so x = ( y - 180.33) / 495.11
where y is the mean value, putting that find x , and then change it in the unit of mg/L . This will be the concentration of quinine in per lite of tonic water.