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How can we measure the rate of a chemical reaction?
Measure the mass of products formed and the time taken
Measure the mass of reactants formed and the time taken
Use a device which measures rate
We cannot measure the rate of a reaction
True or false? The rate of reaction can be found by the equation time/amount of reactant used or product formed.
Which theory states that reactions can only occur if reactants come into contact with one another?
Contact theory
Collision theory
Rutherford's theory of reaction
True or false? The activation energy is the smallest amount of energy needed for a reaction to take place.
Which factor increasing reaction rate would explain why a powder reacts more quickly than a lump of solid?
Temperature is higher
Concentration/Pressure is higher
There is a catalyst
Surface area is larger
Why do particles at high temperature react more frequently?
They are closer together
They collide more frequently
There are more exposed particles to react
They collide with more energy
True or false? If the reaction conditions are increased by 10°C, the rate of reaction will double.
True or false? Increasing the pressure lowers the rate of reaction as there are fewer particles in a given space.
Which of these is likely to have the highest rate of reaction?
1M H2SO4 + 1M KOH
2M H2SO4 + 1M KOH
0.5M H2SO4 + 1M KOH
True or false? Catalysts can only be used once.
What do catalysts do to speed up the rate of reaction?
Lower the activation energy
Provide an alternative route for the reaction
Give the particles more energy
Cause particles to collide more frequently
Which of these are being developed as potential new catalysts?
Nanoparticles
Polymers
Enzymes
Carboxylic acids
True or false? Although transition metals are useful catalysts, their compounds are often toxic.
True or false? Exothermic reactions make the surroundings colder.
Which of these are exothermic reactions?
Combustion
Respiration
Photosynthesis
Neutralisation
Thermal decomposition
Which of these are endothermic reactions?
True or false? A reversible reaction which is exothermic in the forward direction is exothermic in the backward direction.
True or false? Reversible reactions have exactly the same amount of energy lost or gained in both directions.
Which of these is an application of exothermic reactions?
Chemical cold packs
Hand warmers
Which of these is an application of endothermic reactions?