UPSC Combined Geo-Scientist, Mains · 2019 · Mains Paper III
Q4(d). Line and continuum sources
Question
Why is a hollow-cathode lamp used in atomic absorption? Assess the claim that continuous radiation cannot be used.
Answer in brief
A narrow line source matches the very narrow atomic absorption line. The absolute prohibition on continuum sources is incorrect.
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CoversLinecontinuum sourcesAtomic absorption
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