Final answer:
The true statements are C, D, and E. These involve the suitability of HPLC for high molecular weight and thermally labile analytes, the use of spectrometers for detection and identification in chromatography, and the existence of non-destructive HPLC detectors.
Step-by-step explanation:
Which of the following statements are true:
- C. HPLC should be selected instead of GC when dealing with high molecular weight analytes.
- D. Mass spectrometers can be used as detection systems (for HPLC or GC) to assist with analyte identification.
- E. Some HPLC detectors are non-destructive.
Statement A, GC analysis is a suitable technique for thermally labile components, is incorrect as GC is not typically used for thermally labile substances due to the high temperatures involved in the process which can degrade these compounds. Statement B is also incorrect for the same reason, as HPLC, not GC, should be used when analyzing thermally labile analytes to avoid decomposition. On the other hand, high-performance liquid chromatography (HPLC) is a preferred method for separating high molecular weight and thermally labile compounds, making statement C true. Mass spectrometers are indeed versatile detection instruments that can be employed in conjunction with both HPLC and GC systems, providing accurate analyte identification by their mass-to-charge ratio, thus making statement D true. Additionally, certain HPLC detectors, such as refractive index or fluorescence detectors, are non-destructive to the sample, meaning the sample remains intact after analysis, which confirms the truth of statement E.