I got a C in AS, does that mean that it is pretty much impossible for me to get an A overall?
It's not impossible but it may mean that you will have to re-take one or both of your AS exams. It really depends on the UMS you got, you need 240 out of 300 at AS level for an A grade and 480 out of 600 overall for the full A-level.
Do you feel capable of doing the work? I have to ask this because in most cases students tend to drop a grade at A2 due to it being more difficult work which would put your predicted grade at a C/D for the full A-level.
I got a C in AS, does that mean that it is pretty much impossible for me to get an A overall?
Yes, it is impossible for you to get an A. However, it is possible (just very, very hard) for you to get an A*. How difficult depends on your UMS. In the worst case scenario that you literally just scraped a C and got 60% UMS in AS Chemistry, you'd need 100% UMS in A2 Chemistry to get an A overall - which is basically impossible. In the best case scenario that you got the highest possible C (e.g. 69% UMS) then you'd need 91% across A2 Chemistry - which is obviously still very hard.
The reason why you can only get an A* and not an A is because an A* is defined as an A overall, with 90%+ in the A2 modules. Since it's only possible for you to get an A overall by getting above 90% in the A2 modules, you can only get an A*.
So if i can get above 90% in A2 i get A* overall regardless of my AS ? How much would i need to get a B overall?
No, you don't get an A* if you get above 90% in A2 because it depends on what your UMS at AS was. As I mentioned, if you got the highest possible UMS for a C (i.e. you just missed out on a B), then you'd only need a hair over 90% at A2. In the worst case scenario that you literally only just scraped a C, you'd need 100% across the A2.
The score required to get a B also varies, again on your AS results, but the minimum required would be 71% and the maximum required would be 80%.
So if i can get above 90% in A2 i get A* overall regardless of my AS ? How much would i need to get a B overall?
Logically If you've averaged a C at AS you'd need to average an A at A2 to get a B overall at A Level.... Your chances of getting an A overall are almost gone you should just resit to try bump up your grade then give it a go?
No, you don't get an A* if you get above 90% in A2 because it depends on what your UMS at AS was. As I mentioned, if you got the highest possible UMS for a C (i.e. you just missed out on a B), then you'd only need a hair over 90% at A2. In the worst case scenario that you literally only just scraped a C, you'd need 100% across the A2.
The score required to get a B also varies, again on your AS results, but the minimum required would be 71% and the maximum required would be 80%.
I highly doubt the boundary would be 80% for a B :/ that would have to be the easiest chemistry exam paper ever sat tbh
okay so for the 2 exams what would be the maximum percentage i need for a B? In terms of actual paper marks and not UMS
1. We don't know what UMS you're on 2. We don't yet know the grade boundaries
However, as you say maximum I'm going to assume that you got the lowest possible C at AS. Thus you are currently on 180/300. For a B you need 240/300 this year (i.e. an A).
Therefore you'd need maximum 36/40 on practical. 52/60 on unit 1. 80/100 on unit 2.
However depending on your UMS/grade boundaries this could go down significantly.