A gas chromatogram of a mixture of toluene and ethyl (a) Measure w1/2 for each peak to the nearest 0.1 mm. When the thickness of the pen trace is significant relative to the length being measured, it is important to take the pen width into account. It is best to measure from the edge of one trace to the corresponding edge of the other trace, as shown at the bottom of the left column. (b) Find the number of theoretical plates and the plate height for each peak.

You run the chromatography system with paper as the stationary phase and 70% isopropanol as the mobile phase. You determine the Rf  of a polar analyte to be 0.40. If you use 100% isopropanol (a less polar solvent) instead of isopropanol as the mobile phase what would you expect to happen to the Rf  value? No value effect on Rf higher  lower could be higher or lower

A young researcher set out to develop a method for quantifying the polycyclic aromatic hydrocarbon (PAH) content in a contaminated soil sample using open tubular gas chromatography. During the initial stages of method development, the researcher was unable to separate the early eluting compounds, anthracene and naphthalene, with baseline resolution. Select the possible modifications the researcher could make to improve the resolution. use a column with a smaller inner diameter decrease the column length increase the stationary phase thickness increase the temperature choose a different stationary phase

How much iron ore (that assays at 10.18% Fe) must be used in an analytical procedure that is known to have a low bias of −0.15 g if an overall relative error of 0.48 ppth in the iron content is desired?