UPSC Combined Geo-Scientist, Mains · 2022 · Mains Paper I
Q10(a). Initial activity and first-second disintegrations
Question
Calculate the rate of disintegrations that occur in the first second(s) from 1.0 mol of a radioactive material with t₁/₂ = 12000 years, t₁/₂ = 12 hours and t₁/₂ = 12 seconds. Avogadro number = 6.022 × 10²³ mol⁻¹
Model answer
The free solution for 2022 answers questions 1, 2, 4, 7, 8 and 11, the ones picked in its time plan. Question 10 is answered in full in the Geo-Scientist Chemistry Paper I, 2021 to 2025 book, with every part of every paper.
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UPSC Combined Geo-Scientist (Main) Chemistry Paper I: Model Answers 2021 to 2025
- All eleven questions of each paper, with the question printed above its answer
- Titration, gravimetric and nuclear numericals worked with units; structures drawn
- Topic-wise weightage and a topic-wise index
Coversradioactive decay constantactivityhalf-lifedisintegration ratefirst-order decay
All parts of Question 10
- 10(a) Initial activity and first-second disintegrations15 marks
- 10(b) Completing nuclear decay equations5 marks
- 10(c) Geiger-Müller counter10 marks