Chemical Engineering
Conservation laws, transport phenomena, thermodynamics, reactions, approximations .
Building Blocks for Chemical Engineering
Chemical engineering interviews rarely test memorisation. Instead, they are looking for strategic problem solvers who can simplify a messy physical situation into a solvable, idealised model. Typically, this means applying one of a small number of core tools:
Conservation Laws: Mass and energy balances underpin many problems and are applied over a control volume as
Transport Phenomena: A key distinction between chemical engineering and chemistry is scale. At large scales, mixing, heating and cooling become difficult, so many processes are limited by diffusion, fluid flow, and heat transfer.
Thermodynamic Driving Forces: Differences in temperature, concentration, and chemical potential are what cause systems to change.
Reaction & Kinetic Reasoning: Not detailed mechanisms, but understanding rates, orders, limiting steps, and how changing conditions affects behaviour.
Approximations & Scaling: Be bold but sensible. Interviewers want to see whether your approach would work with real numbers, not whether you can calculate them exactly.
Chemical Engineering Mock Interview Scripts
Mixed questions across various topics.
Chemical Engineering FAQs
Generally, no. Oxbridge interviews rarely require specialist knowledge beyond A Level. Instead, interviewers want to see whether you can construct a solution from basic principles.
You might be given a scenario involving a reactor, distillation column, or heat exchanger, which you haven't formally studied. What matters is how you think:
- What goes in and what comes out?
- What is driving the process?
- What limits the rate?
Clear, structured reasoning is far more important than prior technical coverage.
The calculations themselves are usually light; the real challenge is setting up the problem correctly. You may be asked to:
- Write a simple mass or energy balance
- Formulate or interpret a basic differential equation
- Linearise a relationship for small changes
- Use proportional or scaling arguments to predict trends
Mathematics is a tool for expressing your thinking, not the main objective.
No memorisation is expected, but strong physical intuition is.
You should be comfortable explaining ideas such as:
- Why heat flows from hot to cold
- Why gases expand when heated
- Why distillation separates components based on volatility and equilibrium
- Why reactions proceed when ΔG < 0
If a question goes beyond your knowledge, interviewers expect you to extrapolate from simpler systems. They are assessing reasoning, not recall.
The best preparation is practising how to think out loud and explain your reasoning clearly. At the interview stage, extensive reading is far less important than working through unfamiliar problems.
If interviewers were looking for students who already knew the course, they would simply interview chemical engineering graduates from other universities. In fact, being over-prepared can be counterproductive if it appears that you have seen the question before.
This is expected — Oxbridge interviews deliberately go beyond your syllabus.
When this happens:
1. Pause and identify the governing physics (mass balance? heat transfer? diffusion?).
2. State your assumptions explicitly — ideal gas, steady state, negligible losses.
3. Reduce the situation to its simplest workable model.
4. Reason step-by-step, even if you are unsure.
Interviewers are not looking for a perfect answer, but for a clear and logical way of thinking. A simple model with well-explained assumptions is far more impressive than a memorised formula.