Hey!
Well I applied for Chem.Eng last year and got offers from Imperial, UCL, Birmingham and Manchester, with Imperial being my first choice. However I didn't make my Imperial offer,so I'm re-applying again this year. I have a friend in 2nd year at Imperial, and one in 1st year at Cambridge. Apparently it's LOADS of work, so you have to be determined. But then if you're into it and hardworking it's not bad they said.
As for personal statement, they look for genuine enthusiasm for Chemical Engineering. You need to have a good reason why you want to do it. Mention any relevant work experience or anything other than school that would make you a better Chemical engineering student. If you've done like a taster course, you should mention that. Things like books you've read about it, or something that shows your interest in the subject is definitely worth putting in there.
I mentioned work experience and at most of my interviews they asked me about that. They might also ask you an academic question which is quite practical. They don't expect you to know the answer, they just want to see how you process the informationa nd the way you think if that makes sense. If there's a particular industry/aspect of chemical engineering that you'd like to get into, you should definitely mention that. I talked about alternate energy and food and all my interviewers wanted to know more.
Hope that helps!
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