How to get an A* in Physics and Chemistry?

Do you need to be above a certain % to obtain the A*? Or is it similar to Maths, where you need 90+ average in C3 and C4 UMS?
Thanks

Do you need to be above a certain % to obtain the A*? Or is it similar to Maths, where you need 90+ average in C3 and C4 UMS?
Thanks

With reforms, since the abolition of UMS. The council of senior examiners set the 'Raw Mark A* Threshold' post exams. Then everyone including and above this mark is awarded the A*.

The threshold is likely to be equivalent to around 90% UMS in past years anyway so I wouldn't worry, just work very hard

Sources: Rang up OCR to ask the exact question

Oh okay, does this also applies to AQA Chemistry?