The absorbance of benzoic acid (FM 122.12) and caffeine (194.19) standards at two wavelengths, and those of an unknown m
Posted: Tue Nov 23, 2021 8:26 am
The absorbance of benzoic acid (FM 122.12) and caffeine (194.19)
standards at two wavelengths, and those of an unknown mixture of
the two, are shown in the table below. The cuvet size is 1.00 cm.
What is the concentration of benzoic acid
in the original mixture, expressed in mg/L?
λ (nm)
Absorbance of 10.00 mg/L benzoic
acid standard
Absorbance of 20.00 mg/L caffeine standard
Absorbance of unknown mixture benzoic acid and caffeine, prepare
by diluting 2.00 mL of original sample to 100.0 mL
266
0.946
0.489
0.847
320
0.0609
0.937
0.427
standards at two wavelengths, and those of an unknown mixture of
the two, are shown in the table below. The cuvet size is 1.00 cm.
What is the concentration of benzoic acid
in the original mixture, expressed in mg/L?
λ (nm)
Absorbance of 10.00 mg/L benzoic
acid standard
Absorbance of 20.00 mg/L caffeine standard
Absorbance of unknown mixture benzoic acid and caffeine, prepare
by diluting 2.00 mL of original sample to 100.0 mL
266
0.946
0.489
0.847
320
0.0609
0.937
0.427