Q2(c). Slit width that resolves the sodium D lines
Determine the theoretical slit width (in mm, up to 3 decimal places) required for separating the sodium lines at wavelengths 588.9950 nm and 589.5924 nm, using a grating monochromator with a reciprocal linear dispersion of 0.67 nm/mm.
Model answer
The free solution for 2022 answers questions 1, 4, 5, 6, 7 and 10, the ones picked in its time plan. Question 2 is answered in full in the Geo-Scientist Chemistry Paper III, 2021 to 2025 book, with every part of every paper.
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UPSC Combined Geo-Scientist (Main) Chemistry Paper III: Model Answers 2021 to 2025
- All ten questions of each paper, with the question printed above its answer
- Instruments drawn as labelled diagrams, numericals worked with units
- Topic-wise weightage and a topic-wise index
Coversslit widtheffective bandwidthreciprocal linear dispersiongrating monochromatorsodium D lines
All parts of Question 2
- 2(a) Chromium and manganese in steel by spectrophotometry15 marks
- 2(b) Resolution, plate number, plate height and a longer column10 marks
- 2(c) Slit width that resolves the sodium D lines5 marks