How do you measure the rate of a reaction? - correct AnswBy 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 reaction by measuring the amount of reactant
used? - correct AnswMean rate of reaction = quantity of reactant used/time taken
What is the equation for calculating the mean rate of a reaction by measuring the amount of product
formed? - correct AnswMean rate of reaction = quantity of product formed/time taken
What units can you measure the rate of a reaction in? - correct Answg/s or cm3/s or mol/s
How do you calculate the rate of a reaction at a specific time from graph of the quantity of reactant
used or the quantity of product formed? - correct AnswBy measuring the gradient of a tangent drawn at
that specific time on the graph
What are the five factors that can affect the rate of a reaction? - correct AnswConcentration of reactants
in solution, pressure of reacting gases, surface area of solid reactants, temperature and the presence of
a catalyst
What theory can we use to explain how various factors affect the rate of a reaction? - correct
AnswCollision theory
What is collision theory? - correct AnswChemical reactions can occur only when reacting particles collide
with each other and with sufficient energy
What is the activation energy of a reaction? - correct AnswThe minimum amount of energy that
particles must have to react
,According to collision theory why does increasing concentration of reactant in solution increase the rate
of the reaction? - correct AnswIt increases the frequency of collisions and so increases the rate of
reaction
According to collision theory why does increasing the pressure of reacting gases increase the rate of the
reaction? - correct AnswIt increases the frequency of collisions and so increases the rate of reaction
According to collision theory why does increasing the surface area of solid reactants in solution increase
the rate of the reaction? - correct AnswIt increases the frequency of collisions and so increases the rate
of reaction
According to collision theory why does increasing temperature increase the rate of the reaction? -
correct AnswIt increases the frequency of collisions and makes the collision more energetic and so
increases the rate of reaction
How do you increase the surface area of a solid reactant? - correct AnswGrind it into a powder that has
smaller particle size
What effect does increasing the temperature of a reaction by 10°C have on the rate of a reaction? -
correct AnswIt doubles it
What is a catalyst? - correct AnswA 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? - correct AnswBy 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 reaction is a catalyst? - correct AnswIt is not
included in the chemical equation for the reaction
What is a reversible reaction? - correct AnswWhere 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? -
correct Answ
How can you change the direction of a reversible reaction? - correct AnswBy changing the conditions;
for example heating or cooling the reaction
Describe the energy changes in a reversible reaction - correct AnswOne direction will be exothermic and
the other direction endothermic
When is equilibrium in a reversible reaction achieved in apparatus which prevents the escape of
reactants and products? - correct AnswWhen the rate of the forward and reverse reactions occur at
exactly the same rate
What affects the relative amount of all the reactants and products at equilibrium in a reversible
reaction? - correct AnswThe conditions
What happens to an equilibrium if any of the conditions change? - correct AnswThe system responds to
counteract the change
What does Le Chatelier's principle predict? - correct AnswThe effects of changing conditions on a system
at equilibrium
What affect will changing the concentration of one of the reactants in a reversible reaction have on the
equilibrium? - correct AnswThe system will no longer be in equilibrium and the concentration of all the
substances will change until equilibrium is reached again
What happens when the concentration of a reactant is increased in a reversible reaction? - correct
AnswMore products will be formed until equilibrium is reached again
What happens when the concentration of a product is decreased in a reversible reaction? - correct
AnswMore reactant will react until equilibrium is reached again
or the quantity of product formed over time
What is the equation for calculating the mean rate of a reaction by measuring the amount of reactant
used? - correct AnswMean rate of reaction = quantity of reactant used/time taken
What is the equation for calculating the mean rate of a reaction by measuring the amount of product
formed? - correct AnswMean rate of reaction = quantity of product formed/time taken
What units can you measure the rate of a reaction in? - correct Answg/s or cm3/s or mol/s
How do you calculate the rate of a reaction at a specific time from graph of the quantity of reactant
used or the quantity of product formed? - correct AnswBy measuring the gradient of a tangent drawn at
that specific time on the graph
What are the five factors that can affect the rate of a reaction? - correct AnswConcentration of reactants
in solution, pressure of reacting gases, surface area of solid reactants, temperature and the presence of
a catalyst
What theory can we use to explain how various factors affect the rate of a reaction? - correct
AnswCollision theory
What is collision theory? - correct AnswChemical reactions can occur only when reacting particles collide
with each other and with sufficient energy
What is the activation energy of a reaction? - correct AnswThe minimum amount of energy that
particles must have to react
,According to collision theory why does increasing concentration of reactant in solution increase the rate
of the reaction? - correct AnswIt increases the frequency of collisions and so increases the rate of
reaction
According to collision theory why does increasing the pressure of reacting gases increase the rate of the
reaction? - correct AnswIt increases the frequency of collisions and so increases the rate of reaction
According to collision theory why does increasing the surface area of solid reactants in solution increase
the rate of the reaction? - correct AnswIt increases the frequency of collisions and so increases the rate
of reaction
According to collision theory why does increasing temperature increase the rate of the reaction? -
correct AnswIt increases the frequency of collisions and makes the collision more energetic and so
increases the rate of reaction
How do you increase the surface area of a solid reactant? - correct AnswGrind it into a powder that has
smaller particle size
What effect does increasing the temperature of a reaction by 10°C have on the rate of a reaction? -
correct AnswIt doubles it
What is a catalyst? - correct AnswA 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? - correct AnswBy 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 reaction is a catalyst? - correct AnswIt is not
included in the chemical equation for the reaction
What is a reversible reaction? - correct AnswWhere 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? -
correct Answ
How can you change the direction of a reversible reaction? - correct AnswBy changing the conditions;
for example heating or cooling the reaction
Describe the energy changes in a reversible reaction - correct AnswOne direction will be exothermic and
the other direction endothermic
When is equilibrium in a reversible reaction achieved in apparatus which prevents the escape of
reactants and products? - correct AnswWhen the rate of the forward and reverse reactions occur at
exactly the same rate
What affects the relative amount of all the reactants and products at equilibrium in a reversible
reaction? - correct AnswThe conditions
What happens to an equilibrium if any of the conditions change? - correct AnswThe system responds to
counteract the change
What does Le Chatelier's principle predict? - correct AnswThe effects of changing conditions on a system
at equilibrium
What affect will changing the concentration of one of the reactants in a reversible reaction have on the
equilibrium? - correct AnswThe system will no longer be in equilibrium and the concentration of all the
substances will change until equilibrium is reached again
What happens when the concentration of a reactant is increased in a reversible reaction? - correct
AnswMore products will be formed until equilibrium is reached again
What happens when the concentration of a product is decreased in a reversible reaction? - correct
AnswMore reactant will react until equilibrium is reached again
