Topic Colloids
Asked 9 times across 4 UPSC exams over 33 years (1993–2026), peaking in 2026.
Key insights
- Most tested in NDA — 4 of 9 PYQs
- Most asked in 2026
- Recurs across 8 years (1993–2026)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CSE 1993 → CAPF 2016 → CDS 2017 → NDA 2021
How the concept evolved
Rising — more than half its appearances (8 of 9) 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.
NDA2026
Consider the following statements
- A colloid and a suspension are heterogeneous mixtures
- Colloids can be separated from the mixture by the process of centrifugation
- Particles of colloids and suspensions can be seen by naked eye
- The aqueous solution of copper sulphate does not show Tyndall effect; however, the mixture of milk and water shows Tyndall effect
Which of the statements given above is/are correct?
- A I only
- B II and III only
- C I, II and III
- D I, II and IV ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
NDA2026
Consider the following statements
- Pine oil is used as antifoaming agent in the emulsion paints
- Protective colloids are used in the emulsion paints to decrease their stability
- Driers having oxidizable oils are added to the emulsion paints to accelerate drying process
Which of the statements given above is/are correct?
- A I and II
- B I only
- C II and III
- D I and III ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
CDS2024
In which of the following colloids is the dispersing medium a liquid ?
- A Mist
- B Foam
- C Jelly
- D Shaving cream ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
Study how UPSC repeats — not just the papers
₹199 / 1 year · Founding Member
Full access unlocks the three things no PYQ PDF gives you:
① Cross-exam learning — see the same idea recur across CSE, CAPF, CDS and NDA.
② Topic evolution — how each idea is framed, year by year.
③ Question intelligence — every PYQ + answer, linked to related concepts and similar questions.
e.g. Round Table Conference: CDS 2017 → CSE 2017 → … → CAPF 2024
15 days free, no card required — then ₹199 for 1 year.
Start your 15-day free trial →