This page lists GATE CH previous year question papers for 10 years, 2016 to 2026, with 19 official PDFs (question papers and answer keys). GATE CH (GATE Chemical Engineering) is conducted by IISc Bangalore or one of the IITs, in rotation, and covers General Aptitude, Engineering Mathematics and CH core. Pick a year below for the paper, answer key and a timed practice plan; confirm dates and pattern on gate2027.iitm.ac.in.
Year-wise question papers
GATE CH 2026
GATE CH 2026 paper and answer key from IIT Guwahati, 21 NAT and 39 MCQ, 5 MSQ.
GATE CH 2025
GATE CH 2025 paper and answer key from IIT Roorkee, 25 NAT and 36 MCQ, 4 MSQ.
GATE CH 2024
GATE CH 2024 paper and answer key from IISc Bangalore, 22 NAT and 39 MCQ, 4 MSQ.
GATE CH 2023
GATE CH 2023 paper and answer key from IIT Kanpur, 24 NAT and 37 MCQ, 4 MSQ.
GATE CH 2022
GATE CH 2022 paper and answer key from IIT Kharagpur, 30 NAT and 35 MCQ.
GATE CH 2020
GATE CH 2020 question paper with answer key from IIT Delhi, 20 NAT and 45 MCQ.
GATE CH 2019
GATE CH 2019 paper and answer key from IIT Madras, 26 NAT and 39 MCQ.
GATE CH 2018
GATE CH 2018 paper and answer key from IIT Guwahati, 26 NAT and 39 MCQ.
GATE CH 2017
GATE CH 2017 paper and answer key from IIT Roorkee, 29 NAT and 36 MCQ.
GATE CH 2016
GATE CH 2016 paper and answer key from IISc Bangalore, 23 NAT and 42 MCQ.
Not hosted: 2021. We could not retrieve a complete CH PDF from an official GATE site or its Internet Archive capture for that year, so no page is shown rather than a partial file.
Answer first
For GATE CH (CH), solve paper-code-specific previous year questions under timed conditions, keep General Aptitude alive weekly, and build a subject-weight tally from every CH paper you can get. Mixed-branch PDF dumps destroy the signal you need.
Why CH-only PYQs matter
- Official structure: Chemical Engineering has its own subject mix: Engineering Mathematics, Process Calculations and Thermodynamics, Fluid Mechanics and Mechanical Operations, Heat Transfer and more.
- NAT precision: Typed-answer questions reward unit discipline and the rounding range printed in the key. Log a correct setup with a wrong unit as a silly miss.
- MSQ logic: From 2021 the keys include multi-select questions, which score only when every correct option, and no wrong one, is chosen. Practise them with a written option audit.
- M.Tech, PhD and PSU alignment: The same CH papers feed several goals, with different cut-off arithmetic.
Pattern snapshot (verify brochure)
Single paper, computer-based, three hours. 65 questions for 100 marks: 10 General Aptitude (15 marks) and 55 Chemical Engineering questions (85 marks, with Engineering Mathematics inside the core). Question types are MCQ, NAT and, from 2021, MSQ. Wrong MCQ answers lose 1/3 or 2/3 of the question’s marks; MSQ and NAT have no negative marking.
| Block | Role in CH prep |
|---|---|
| General Aptitude | Fixed short daily or weekly block; high ROI marks |
| Engineering Mathematics | Weekly NAT pairs from sticky chapters |
| Core CH | Subjects chosen from your own paper tally; MSQ option audits |
Core topic map for GATE CH
Engineering Mathematics
Linear algebra, calculus, differential equations, complex variables, probability and statistics, numerical methods.
Process Calculations and Thermodynamics
Material and energy balances, recycle and purge, thermodynamic laws, phase and chemical equilibrium, equations of state.
Fluid Mechanics and Mechanical Operations
Fluid statics and flow, pumps, flow measurement, particle size, filtration, settling, mixing, size reduction.
Heat Transfer
Conduction, convection, radiation, heat exchangers, evaporators, boiling and condensation.
Mass Transfer
Diffusion, mass transfer coefficients, distillation, absorption, extraction, adsorption, drying, humidification, membranes.
Chemical Reaction Engineering
Reaction kinetics, ideal reactors, residence time distribution, non-ideal flow, catalysis and diffusion limits.
Instrumentation and Process Control
Measurement devices, transfer functions, dynamic response, feedback control, stability.
Plant Design and Economics
Process design, equipment sizing basics, costing, depreciation, profitability.
Chemical Technology
Process industries: water, fertilisers, petroleum refining, petrochemicals, polymers, pulp and paper.
Pareto guidance: Mark counts per subject are not tabulated on this hub, so build your own tally. After each paper, count how many questions each subject contributed and let the running average decide your order of study.
Prep timelines using CH PYQs
3-month plan
In month 1, sit one full CH paper to see where you stand, and work on your three weakest areas. In month 2, practise CH PYQs subject by subject, starting with the ones that carry the most marks in your tally. In month 3, alternate full papers with revising the formulas from your error log.
6-month plan
Finish the syllabus with weekly CH PYQ tagging. In the second half, sit one full paper most weeks plus subject revision from misses only. Use older papers for topic drills and keep the latest two years for timed mocks.
12-month plan
Syllabus, then subject-wise CH PYQs, then full papers, then revision cycles. Keep GA alive all year. Common weak spots to watch: Process calculations, thermodynamics, mass transfer and reaction engineering.
Common mistakes
- Solving mixed-paper dumps from other GATE codes.
- Ignoring the latest official CH syllabus PDF.
- No NAT re-entry practice.
- Skipping GA because core feels endless.
FAQ
Where can I find GATE CH previous year question papers?
On this hub: the official Chemical Engineering papers and answer keys for 10 of the 11 years from 2016–2026, from the organising institutes’ sites. Each year page links the original source.
How many years of GATE CH PYQs should I solve?
Aim for 8-10 recent years of paper code CH for subject weightage, with every recent year timed at least once.
Are GATE CH PYQs enough?
They are the best practice available, but they do not replace the official syllabus, studying the concepts, and keeping up General Aptitude and Engineering Mathematics.
Should I mix other GATE paper codes with CH?
No for core subject practice. GA can be cross-practised and mathematics templates transfer, but core questions should stay CH-only.
How should I use an error log?
Same day: tag each miss by block (GA, mathematics, core), subject, and miss type (concept, silly, time or misread). Next sessions repair logged items only.
Where to get the official papers
GATE CH question papers, answer keys and notifications are published by the IISc or IIT organising that year’s exam on its own GATE website (IIT Madras for GATE 2027: gate2027.iitm.ac.in). Download them from there. We link to the official files and add practice notes, but the latest official notification is the final word on dates, pattern and eligibility.