C2.4- Rates of reaction Flashcards
State 4 factors that increase rate or reaction
Surface area
Concentration
Temperature
A catalyst
What must happen for a reaction to occur between 2 particles?
They have to collide
With enough energy
What does activation energy mean?
The minimum amount of energy needed to start a reaction
How does increasing the temperature effect the rate of reaction?
The kinetic energy of the particles increases so there are more frequent successful collisions
How could you increase the surface area of a solid reactant?
Crush it/ chop it up
What does a catalyst do?
It lowers the activation energy of a reaction, so there are more frequent successful collisions
How does decreasing the concentration effect the rate of reaction?
There are less particles in the same volume therefore there are less frequent successful collisions
How does increasing the surface area effect the rate of reaction?
There are more reactant particles exposed, so there are more frequent successful collisions
Explain the shape of this rate graph and identify 3 key stages
Rate is fastest at the start of the reaction
Rate slows as reactants get used up
Rate drops to zero(reaction has finished)
What two equations can work out the rate of reaction?
Amount of reactant used up/ time taken
Products formed/time taken
Describe this method for measuring the rate of reaction
The mass of the contents decreases as the co2 produced is released during the reaction.
The time is measured as the mass of the reactants decreases
Describe this method for measuring the rate of reaction.
The flask turns from colourless to a white cloudy suspension as sulfur is produced in the reaction.
The time it takes for the cross under the flask to ‘disappear’ is measured
Describe this method for measuring the rate of reaction
The volume of the product gas increases during the reaction
The time taken to collect a set volume of product gas is measured
