Question

The more sensitive detector in gas chromatography is _______ detector.

• A. \( \text{Flame ionization} \)
• B. \( \text{Thermal conductivity} \)
• C. \( \text{Electron capture} \)
• D. \( \text{Thermoionic} \)

Hint:

Remember ECD as the "electron snatcher" – it's super good at detecting things that grab electrons, making it very sensitive for those compounds.

Answer 1

The Correct Option is C

Gas chromatography (GC) employs various detectors to detect the separated analytes as they elute from the column. The sensitivity of these detectors varies depending on the type of analyte. Among the given options, the electron capture detector (ECD) is generally considered the most sensitive, particularly for compounds with electronegative atoms or functional groups, such as halogens, phosphorus, and nitro groups. ECD works by measuring the decrease in a standing current caused by the capture of electrons by the eluted compounds. While flame ionization detectors (FID) are widely used and sensitive to hydrocarbons, ECD offers higher sensitivity for specific types of compounds. Thermal conductivity detectors (TCD) are universal but less sensitive. Thermoionic detectors (TID) are highly sensitive and selective for compounds containing nitrogen or phosphorus.