AQA GCSE Chemistry Paper 2 2026 |
Practice Questions, Answers, Required
Practicals & Complete Revision Guide |
Complete Ethics Study
Guide
Updated 2026 Questions and Answers
100% Verified Exam Prep and Comprehensive
Rationales
Included
,How do you measure the rate of a reaction? By measuring the quantity of a reactant used or the quantity of product formed over
time
What is the equation for calculating the mean rate of a Mean rate of reaction = quantity of reactant used/time taken
reaction by measuring the amount of reactant used?
What is the equation for calculating the mean rate of a Mean rate of reaction = quantity of product formed/time taken
reaction by measuring the amount of product formed?
What units can you measure the rate of a reaction in? g/s or cm3/s or mol/s
How do you calculate the rate of a reaction at a specific By measuring the gradient of a tangent drawn at that specific time on the graph
time from graph of the quantity of reactant used or the
quantity of product formed?
What are the five factors that can affect the rate of a Concentration of reactants in solution, pressure of reacting gases, surface area of
reaction? solid reactants, temperature and the presence of a catalyst
What theory can we use to explain how various factors Collision theory
affect the rate of a reaction?
What is collision theory? Chemical reactions can occur only when reacting particles collide with each other
and with sufficient energy
What is the activation energy of a reaction? The minimum amount of energy that particles must have to react
According to collision theory why does increasing It increases the frequency of collisions and so increases the rate of reaction
concentration of reactant in solution increase the rate of
the reaction?
According to collision theory why does increasing the It increases the frequency of collisions and so increases the rate of reaction
pressure of reacting gases increase the rate of the
reaction?
According to collision theory why does increasing the It increases the frequency of collisions and so increases the rate of reaction
surface area of solid reactants in solution increase the rate
of the reaction?
According to collision theory why does increasing It increases the frequency of collisions and makes the collision more energetic and
temperature increase the rate of the reaction? so increases the rate of reaction
How do you increase the surface area of a solid reactant? Grind it into a powder that has smaller particle size
What effect does increasing the temperature of a reaction It doubles it
by 10°C have on the rate of a reaction?
, What is a catalyst? A chemical that changes the rate of a chemical reaction but is not used up in the
reaction
How do catalysts increase the rate of a reaction? By providing a different pathway for the reaction that has a lower activation energy
How do you know in a reaction that a chemical is used in a It is not included in the chemical equation for the reaction
reaction is a catalyst?
What is a reversible reaction? Where the products of a chemical reaction can react to produce the original
reactants
What is the symbol used in reversible reaction equations
that shows that the reaction is reversible?
How can you change the direction of a reversible reaction? By changing the conditions; for example heating or cooling the reaction
Describe the energy changes in a reversible reaction One direction will be exothermic and the other direction endothermic
When is equilibrium in a reversible reaction achieved in When the rate of the forward and reverse reactions occur at exactly the same rate
apparatus which prevents the escape of reactants and
products?
What affects the relative amount of all the reactants and The conditions
products at equilibrium in a reversible reaction?
What happens to an equilibrium if any of the conditions The system responds to counteract the change
change?
What does Le Chatelier's principle predict? The effects of changing conditions on a system at equilibrium
What affect will changing the concentration of one of the The system will no longer be in equilibrium and the concentration of all the
reactants in a reversible reaction have on the equilibrium? substances will change until equilibrium is reached again
What happens when the concentration of a reactant is More products will be formed until equilibrium is reached again
increased in a reversible reaction?
What happens when the concentration of a product is More reactant will react until equilibrium is reached again
decreased in a reversible reaction?
Practice Questions, Answers, Required
Practicals & Complete Revision Guide |
Complete Ethics Study
Guide
Updated 2026 Questions and Answers
100% Verified Exam Prep and Comprehensive
Rationales
Included
,How do you measure the rate of a reaction? By measuring the quantity of a reactant used or the quantity of product formed over
time
What is the equation for calculating the mean rate of a Mean rate of reaction = quantity of reactant used/time taken
reaction by measuring the amount of reactant used?
What is the equation for calculating the mean rate of a Mean rate of reaction = quantity of product formed/time taken
reaction by measuring the amount of product formed?
What units can you measure the rate of a reaction in? g/s or cm3/s or mol/s
How do you calculate the rate of a reaction at a specific By measuring the gradient of a tangent drawn at that specific time on the graph
time from graph of the quantity of reactant used or the
quantity of product formed?
What are the five factors that can affect the rate of a Concentration of reactants in solution, pressure of reacting gases, surface area of
reaction? solid reactants, temperature and the presence of a catalyst
What theory can we use to explain how various factors Collision theory
affect the rate of a reaction?
What is collision theory? Chemical reactions can occur only when reacting particles collide with each other
and with sufficient energy
What is the activation energy of a reaction? The minimum amount of energy that particles must have to react
According to collision theory why does increasing It increases the frequency of collisions and so increases the rate of reaction
concentration of reactant in solution increase the rate of
the reaction?
According to collision theory why does increasing the It increases the frequency of collisions and so increases the rate of reaction
pressure of reacting gases increase the rate of the
reaction?
According to collision theory why does increasing the It increases the frequency of collisions and so increases the rate of reaction
surface area of solid reactants in solution increase the rate
of the reaction?
According to collision theory why does increasing It increases the frequency of collisions and makes the collision more energetic and
temperature increase the rate of the reaction? so increases the rate of reaction
How do you increase the surface area of a solid reactant? Grind it into a powder that has smaller particle size
What effect does increasing the temperature of a reaction It doubles it
by 10°C have on the rate of a reaction?
, What is a catalyst? A chemical that changes the rate of a chemical reaction but is not used up in the
reaction
How do catalysts increase the rate of a reaction? By providing a different pathway for the reaction that has a lower activation energy
How do you know in a reaction that a chemical is used in a It is not included in the chemical equation for the reaction
reaction is a catalyst?
What is a reversible reaction? Where the products of a chemical reaction can react to produce the original
reactants
What is the symbol used in reversible reaction equations
that shows that the reaction is reversible?
How can you change the direction of a reversible reaction? By changing the conditions; for example heating or cooling the reaction
Describe the energy changes in a reversible reaction One direction will be exothermic and the other direction endothermic
When is equilibrium in a reversible reaction achieved in When the rate of the forward and reverse reactions occur at exactly the same rate
apparatus which prevents the escape of reactants and
products?
What affects the relative amount of all the reactants and The conditions
products at equilibrium in a reversible reaction?
What happens to an equilibrium if any of the conditions The system responds to counteract the change
change?
What does Le Chatelier's principle predict? The effects of changing conditions on a system at equilibrium
What affect will changing the concentration of one of the The system will no longer be in equilibrium and the concentration of all the
reactants in a reversible reaction have on the equilibrium? substances will change until equilibrium is reached again
What happens when the concentration of a reactant is More products will be formed until equilibrium is reached again
increased in a reversible reaction?
What happens when the concentration of a product is More reactant will react until equilibrium is reached again
decreased in a reversible reaction?
