Graduate Chemical Engineer Interview Questions UK: 8 Real Questions and What Interviewers Want

Before your Graduate Chemical Engineer interview, it helps to see the questions from the interviewer's side. We have picked eight from our set of 12 and added the reason each one gets asked.

Eight Graduate Chemical Engineer interview questions, and what the interviewer is thinking

1. Why did you choose chemical engineering, and what do you expect to be doing in your first year as a graduate?

Why they ask: To check your motivation and whether your expectations of graduate work are realistic.

2. How would you set up a steady-state mass balance for a process with a recycle stream and a purge?

Why they ask: To test fundamental process engineering skills that graduates use daily.

3. Explain how a shell and tube heat exchanger works and what affects its performance over time.

Why they ask: To check understanding of one of the most common pieces of plant equipment.

4. How does a centrifugal pump work, and what are NPSH and cavitation?

Why they ask: To see if you understand pumping basics and a classic process problem.

5. What's the difference between a PFD and a P&ID, and what would you check when reviewing a P&ID?

Why they ask: To check you can read the drawings used across every process plant.

6. Tell me about your final-year design or research project, and what you personally contributed.

Why they ask: To see how you apply technical learning and describe your own contribution.

7. On a placement, you see an experienced operator carrying out a task without following the written procedure. What do you do?

Why they ask: To test safety courage and your approach as a junior to a more senior colleague.

8. Your calculated flow rate for a pump line is 20 per cent different from the plant's measured value. What would you do?

Why they ask: To test critical thinking about data, assumptions and instruments, which graduates face often.

A sample answer to question 1

Why did you choose chemical engineering, and what do you expect to be doing in your first year as a graduate?

I chose chemical engineering because it combines chemistry, physics and maths to solve practical problems at scale, and the impact is real: making medicines, cleaner fuels, food or materials safely and efficiently. During my degree, I enjoyed process design and the way a single change to temperature or flow can affect the whole plant. In my first year, I expect to be learning rather than leading. That probably means rotations or placements across production, process engineering and technical or safety teams. I'd be supporting engineers with mass and energy balances, data analysis, P&ID checks, plant trials, equipment inspections and minor improvement projects, while spending real time on the plant with operators to understand how things run in practice. I'd also expect to take on site safety training, and to work towards chartership with the IChemE, building evidence against the competences along the way. I want to become someone operators and managers trust to find sensible, safe solutions.

Common mistake to avoid: Overstating your readiness to lead; giving a generic 'I like chemistry' answer

Want the rest?

Full model answers, key points and common mistakes for all 12 questions are on the Graduate Chemical Engineer interview questions page. The first five are free, no sign-up needed.