Topic Diffusion
Asked 3 times across 3 UPSC exams over 2 years (2022–2024), peaking in 2024.
Key insights
- Most tested in NDA — 1 of 3 PYQs
- Most asked in 2024
- Recurs across 2 years (2022–2024)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
ESE 2022 → NDA 2024 → GEO 2024
How the concept evolved
Rising — more than half its appearances (3 of 3) are since 2016.
Related concepts
Ideas UPSC tests alongside this one — keep exploring.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
NDA2024
The intermixing of particles of two different types of matter on their own is called
- A Osmosis
- B Brownian motion
- C Diffusion ✓
- D Conductance
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
GEO2024
Which one of the following processes describes the movement of particles or molecules from a region of higher concentration to a region of lower concentration ?
- A Diffusion ✓
- B Osmosis
- C Plasmolysis
- D Deplasmolysis
✓ Correct answer: (A)
Science & Technology › Biology & Health
ESE2022
Which one of the following is NOT a classification of microscopic diffu sion?
- A Inter-diffusion
- B Vacancy diffusion ✓
- C Surface diffusion
- D Lattice diffusion Many bulk polymers that are crystal
✓ Correct answer: (B)
Engineering › Mechanical
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