Science 10:
Reaction Rate
Learning
outcomes 20, 21
REACTION RATE:
Reaction Rate (AKA Rate of Reaction)
• How quickly or slowly your reactants turn into
products.
Eg. From our last lab:
High reaction rate Low reaction rate
Factors Affecting Reaction Rate:
1) Temperature:
• High temperature = Higher rate of reaction
• Low temperature = Lower rate of reaction
How:
• Kinetic molecular theory: Particles move faster
when you heat them up = more collisions
Factors Affecting Reaction Rate:
2) Concentration:
• Low concentration = low reaction rate
• High concentration = high reaction rate
How: The reactants are more likely to bump into
each other
Low Concentration
High Concentration
Factors Affecting Reaction Rate
3) Surface Area:
• A lot of surface area available = high reaction rate
• A low amount of surface area = low reaction rate
How:
• High surface area means there is a large amount of
reactants available to react with.
• Eg. Burning wood: A solid 2kg log burns slowly
A 2kg bunch of twigs burns fast
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Factors Affecting the Reaction Rate
4) Catalyst:
• A catalyst is a substance that speeds up the
reaction rate without being used up in the
reaction.
How?
• A catalyst will line up molecules so that when
they collide they will react. This reduces the
amount of energy that is needed in a reaction
Assignment
Review Questions:
Reaction rates and Reaction types
Next class final Chem review
Test on Tuesday