Is one week enough to solve past papers?

I'm talking about GCSE. How many past papers do I need to solve to get an A*? For example, I've finished the chemistry specification and I have one week until the exam. Do you think that's too short? How many past papers should I solve every day for every subject?

It really depends! I wouldn't worry too much though- spend the time doing them and revising for your other subjects then you have the best chance it sounds like you've done a fair bit already so hopefully you're pretty well prepared! Do one completely and see which areas you need to work on, try and mark yourself quite harshly too so it's worst case scenario as it were. Pay attention to the mark scheme too when you're doing that- what sort of stuff do you need to write to get the marks? Is there any way you could get more marks without actually doing any more learning? In terms of how many, just do what you can, make sure you eat/sleep/exercise well too as these are if anything more important at this stage. You'll be alright!