Hi, I’m Gillian, a second year Chem Eng. I did Chem Eng via NatSci, and chose Physics, Materials, Chemistry and Maths for my first year options. Even if you didn’t apply originally for Chem Eng, you can still switch to it after your first year of NatSci (or Engineering) – it doesn’t matter too much which options you’ve done, but Chemistry will be helpful.
The department run a few open days in Lent and Easter term that you can go along to if you’re thinking about switching to find out more about the subject and course.
If you have any questions feel free to email me at firstname.lastname@example.org
Chem eng course website: http://www.ceb.cam.ac.uk/undergraduates/prospective-students