UPSC Combined Geo-Scientist, Mains · 2019 · Mains Paper III
Q4(f). TCD versus FID response
Question
Why is TCD broadly responsive whereas FID is not universal?
Answer in brief
TCD senses thermal-conductivity differences; FID requires formation of ions from suitable combustible analytes.
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CoversTCDFID responseGas chromatography
All parts of Question 4
- 4(a) Sulfur chloride formula5 marks
- 4(b) Absorbance and transmittance5 marks
- 4(c) Beer-law deviations5 marks
- 4(d) Line and continuum sources5 marks
- 4(e) Background-correction methods5 marks
- 4(f) TCD versus FID response5 marks