UPSC Combined Geo-Scientist, Mains · 2025 · Mains Paper III

Q3(c). Globar as an IR source; advantage over the Nernst glower

10 marks
Topic: Spectroscopic methods of analysis
Question only

Question

What is a Globar and how does it act as an IR source? What is the advantage of Globar as compared to Nernst Glower?

Model answer

The free solution for 2025 answers questions 1, 2, 4, 6, 7 and 9, the ones picked in its time plan. Question 3 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

Printed copy Kindle edition Read sample pages

Topic notes: spectroscopic instruments (Beer–Lambert law, UV–vis and IR instruments, Job's method, AAS and flame emission), with every Civil Services, IFoS and Geo-Scientist PYQ →

CoversGlobarNernst glowerIR sourcesilicon carbideIR instrumentation

All parts of Question 3

3(a) Calcium in a phosphate medium by AAS; protective agents15 marks
3(b) Two-line background correction in AAS5 marks
3(c) Globar as an IR source; advantage over the Nernst glower10 marks