procedure:
Using a stock solution of ethanol (100%), a series of standards of ethanol in water at concentration of 0,2,4,6,8,10 were prepared and 1ml of standard 1-butanol was added to each of the sample.
% ethanol EtOH
ml BuOH
ml Water
ml Total volume
ml
0 0 1 24.0
2 0.5 1 23.5 25
4 1 1 23 25
6 1.5 1 22.5 25
8 2 1 22 25
10 2.5 1 21.5 25
• 1ul of each of the standards were injected and recorded the retention time and the corresponding peak areas for ethanol and 1-butanol.
• 1ul of supplied gripe water was injected onto the GC and recorded a chromatogram for 4min approx. and recorded the peak areas.
• A calibration curve of peak area ratio (PAR) and ethanol concentration (%) was prepared using the data obtained from the ethanol standards.
• The PAR for the gripe water sample was calculated and the % ethanol in the sample was determined by interpolation.
RESULT:-
= 1.44%
% ethanol Peak area
EtOH
Peak area
BuOH
PAR Total volume
ml
0 0 285506 0 25
2 76691 175598 0.436 25
4 139683 183237 0.762 25
6 275208 188446 1.0460 25
8 329509 178345 1.0847 25
10 375101 156907 2.390 25
Gripe water 417610 240070 1.739 1 ul
Calculation
from graph
y = 0.2026x - 0.0597
1.739 = 0.2026x – 0.0597
X = 8.87
calculation
Error calculation:
The actual alcohol % = 90%
how can i find the percentage error ..is my calculation correct or not?
?? i got huge error ...what i do.....plz help me