UPSC Combined Geo-Scientist
Chemist
- 3 descriptive papers
- 200 marks each
- 3 h per paper
Mains Paper III covers analytical and organic chemistry.
All topics
Mains Paper III, analytical and organic chemistry
Thermal methods of analysis: every question, 2016 to 2025
14 parts worth 90 marks have been set on this unit in UPSC Geo-Scientist Chemistry Mains Paper III from 2016 to 2025. Each one opens on its own page with the question, the answer in brief and the key points.
Syllabus
Theory of thermogravimetry (TG), basic principle of instrumentation, techniques for quantitative analysis of Ca and Mg compounds.
Notes: Thermal methods: thermogravimetry (TG), DTG and DTA, with Ca and Mg analysis (full notes) · short notes
2025
- Q1(e) Heating rate, particle size and heat of reaction in TGA5 marks Answered
- Q4(a) CaCO₃ in a CaCO₃–CaO mixture from the TG mass loss10 marks Answered
2024
- Q1(d) Identifying a magnesium compound from its thermogram5 marks Answered
- Q2(c) Furnace atmosphere and the TG curve; CaC₂O₄·H₂O in O₂ and N₂10 marks Question only
2023
- Q1(e) Calibration of the temperature axis in thermogravimetry5 marks Answered
- Q2(c) CaCO₃ and MgCO₃ in a dolomite sample from its thermogram10 marks Question only
2022
- Q1(e) Components of a thermogravimetric analyser5 marks Answered
- Q4(c) Thermogram of calcium oxalate monohydrate5 marks Answered
2021
- Q4(c) Scanning and isothermal thermogravimetry; the thermobalance5 marks Question only
- Q5(c) MgSO₄·7H₂O in a sample from the TG mass loss5 marks Answered
2020
- Q1(d) Thermobalance5 marks Answered
- Q2(d) Calibration of TGA5 marks Answered
- Q3(a) Thermogravimetry of Ca, Ba and Sr oxalate monohydrates10 marks Question only
2017
- Q1(g) Proximate analysis by TGA5 marks Answered
Printed copy and Kindle
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