A mixture containing 18.8 ?M of theanalyte of interest and 44.4 ?M of the internal standard producedchromatographic peak areas of 306 for the analyte and 511 for thestandard. A second solution containing an unknown quantity of theanalyte and 55.5 ?M of the internal standard produced peak areas of251 for the analyte and 563 for the internal standard.

What is the concentration of theanalyte in the second solution expressed as ?M?

answers

watching

views

For unlimited access to Homework Help, a Homework+ subscription is required.

Join us on Discord

Chemistry Study Group

Join now

Related questions

A known standard mixture of pseudoephedrine (A) and 4-aminoacetophenone (B;
internal standard, IS) and an unknown urine sample gave the following GC data (using
a 30-m HP5 capillary column held at 260Â° C).
Compound A Concentration 500 ug/mL - Peak Area 141.2
Compound B Concentration 500 ug/mL - Peak Area 119.9
A in urine sample Concentration unknown - Peak Area 147.7
B added to urine sample Concentration (calc from below) - Peak Area 218.9

A 5.00 mL urine sample was taken for GC analysis. To this sample was added 100 Î¼L
of the 5 mg/mL of the internal standard (B). The mixture was then treated with ammonia
and passed through a RP18 SPME cartridge. The analyte and internal standard were
both retained on the SPME cartridge and were then eluted with 2.0 mL methanol. The
eluate was evaporated down to about 0.5 mL and 1 Î¼L of this concentrate was
analysed by GC. The observed retention times and peak areas obtained for the signals
are included in the table above.
What was the concentration (in Î¼g/mL) of A in the urine?
(peak area of analyte signal)/(analyte concentration) = F (peak area of IS signal)/ (IS concentration)

This is a prior exam question example rather than a real world result. This is all the information the lecturer has provided for a 10 point exam question. I'm expecting the calculations are to be done from concentration and peak area per the formula rather than using retention time and creating a calibration curve. Needing help with the dilution calculation for the B+sample concentration please.