All of the questions of this on Chegg are incorrect. I guessed the answers above
ID: 568644 • Letter: A
Question
All of the questions of this on Chegg are incorrect. I guessed the answers above and it's incorrect. Thank you!
Match the detector or detectors that can be used in gas chromatography for the detection of the following list of analytes by dragging the detector into the box to the left of the analyte. (More han one detector may be appropriate for a given analyte, and a given detector may be appropriate for more than one group of analytes.) thermal thermal conductivity flame photometric electron capture conductivity Carbon atoms bearing hydrogen atoms P and S and other elements selected by wavelength flame nit spectrometer sulfur chemiluminescence thermal conductivity thermal conductivity electron capture thermal conductivity Molecules with halogens, CN, NO2. conjugated C-O P and N (and also hydrocarbons) n- mass flame lame onization thermal conductivity thermal conductivity mass Aromatic and unsaturated compounds mass mass spectrometerExplanation / Answer
As mentioned, Gas-chromatography is used.
From left part and 1 to 3
1. For carbon atoms bearing hydrogen, both thermal conductivity and flame ionization are used. For example, methane molecule (CH4) is detected by both thermal and flame ionization detetector.
2. In this case, thermal conductivity and mass spectroscopy are used. Especially for detecing C=O bonds, the mass spectroscopy can be used if the molecule is complex.
3. Mass spectroscopy (MS) is the most relevant here for detecting aromatics. This is also referred as ESI-MS i.e. electrospray ionization.
From right part
For nitrogenous and suplur containing compounds, the thermal conductivity detector can be used. Such instruments are used in detecting NO, NO2, SO2 in the flue gas analysis. In addition, luminiscence technique for phosphorous and sulphue can be used if concentrations are in ppm (parts per million).