The results recorded here show that the reaction had finished by four minutes, as no more gas was produced after that. The mean rate of reaction = 50 ÷ 4 = 12.5 cm 3 /min However, the rate decreased ...

Here you can find AQA past papers for GCSE chemistry. Use the links below to download question papers and mark schemes. If you’re unsure whether you need Foundation or Higher papers, consult your ...