Original post by 5hyl33nHi!
I take Chemistry A-Level so I can only speak for that. Also, I am in year 12, so hopefully someone who is in year 13 or at university can give you more advice!
In regards to your current options, both subjects are well-suited. If you take Biology, Chemistry and Maths, you are keeping more doors open for yourself. If you have a change of heart, you could even go into Medicine or a Science route as usually you will need two Sciences.
A-Level Chemistry is a difficult subject but like all A-Levels if you keep on top of your work and ask for help whenever you don't understand something straight away, you will be absolutely fine!
If you are still confused, how about you take all 4 subjects (Biology, Chemistry, Maths and Economics) and drop the one later you are finding more difficult or take it as an AS?
If you have anymore questions about Chemistry, either PM me or mention me in this thread and I will give you more information.
If you want some examples on what A-Level Chemistry consists of, I can screenshot a few pages of the textbook and send it to you.
Perhaps, look for past papers on both subjects and see how they look (beware, Chemistry may look intimidating at first, but it is not that bad!)
Good luck!