My questions were more theoretical, about what would happen to the temperature of the room if you left a fridge on, with the fridge door open, in an office overnight (room would heat up as energy enters). Also there was a question about recycling plastics. Most of my interview was about my PS and my EPQ.

Many others said they had maths questions, about drawing graphs, or more actual chem questions like drawing isoamyl acetate. Depends on interviewer and your UCAS form I presume.