C8.1 Rates of Reaction Flashcards
How can you work out the rate of a chemical reaction? (2)
The rate of a chemical reaction can be found by measuring the quantity of a reactant used or the quantity of product formed over time:
mean rate of reaction = quantity of reactant used / time taken
mean rate of reaction = quantity of product formed / time taken
How can the quantity of reactant or product be measure? (2)
The quantity of reactant or product can be measured by the mass in grams, by a volume in cm3.
What are the units for rate of reaction? (2)
The units of rate of reaction may be given as g/s or cm3/s.
When will a chemical reaction occur? (2 marks)
When reacting particles collide with each other AND with sufficient energy
How can a graph of time vs amount of product produced be used to compare rates of reaction? (2 marks)
The steeper the gradient, the faster the reaction.
What does it mean when the graph levels off and goes flat? (1 mark)
It means the reaction is complete and no more product is being produced
Why do the lines curve before levelling off/going flat? (2 marks)
As the reaction proceeds the concentration of reactants decreases, decreasing the rate of reaction, so the gradient decreases.
As the reaction proceeds, the concentration of product increases, which further decreases the concentration of reactants, decreasing the rate of reaction, so the gradient decreases.
