Chemistry Paper 2 GCSE AQA Foundation Q: What is an equilibrium? A: the condition existing when a chemical reaction and its reverse reaction proceed at equal rates. Q: What is a Catalyst? A: speeds up a reaction

AQA GCSE Chemistry Paper 2 QUESTION: How would you describe the pH of carbon dioxide ANSWER: slightly acidic QUESTION: Why is it bad for plastic bags to be burned ANSWER: Release toxic gases that are bad for human health and release greenhouse gases that harm the environment

AQA GCSE Chemistry Paper 2 QUESTION: How do you measure the rate of a reaction? ANSWER: By measuring the quantity of a reactant used or the quantity of product formed over time QUESTION: What is the equation for calculating the mean rate of a reaction by measuring the amount of reactant used? ANSWER: Mean rate of reaction = quantity of reactant used/time taken

GCSE Chemistry Paper 2 activation energy: minimum amount of energy needed for a reaction to occur why does increasing the temperature increase the rate of reaction? particles have more kinetic energy more frequent collisions collisions are harder and more successful

QUESTIONS AND ANSWERS

QUESTIONS AND ANSWERS

GCSE BIOLOGY 8461/2H Paper 2 Higher Tier Mark scheme June 2019 Version: 1.0 Final *196G 4612h/MS* FINAL MARK SCHEME GCSE BIOLOGY 2H Mark schemes are prepared by the Lead Assessment Writer and considered, together with the relevant questions, by a panel of subject teachers. This mark scheme includes any amendments made at the standardisation events which all associates participate in and is the scheme which was used ...