Uploaded by Nuno Oliveira

Reaction Rate Chemistry

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Reaction Rate
Reaction Rate
In chemistry we can have Slow and Fast reactions…
Reaction Rate
Example of slow reactions…
Example of fast reactions…
Zinc + Hydrochloric Acid
Concrete setting
Rust forming
Burning
Reaction Rate
But is not always enough to know just how fast or slow a reaction is…. Examples?
Sometimes we need to know exactly how fast a
reaction goes, and how long it will take to be finished
Reaction
Rate!
Reaction Rate
Measure of the change that happens in a single unit of time
The rate of reaction is found by measuring the
amount of a reactant used up per unit of time, or the
amount of a product produced per unit of time.
Let`s get Practical!!!!!
Reaction Rate
Reactant
Concentration
Factors affecting the
rate of reaction
Temperature
Catalyst
Surface area
Reaction Rate – changing the rate
Changing the reactant concentration
Lets make a graph
Reaction Rate – changing the rate
A reaction goes faster when the concentration of a
reactant is increased
Reaction Rate – changing the rate
Changing the temperature
Why do we use the fridge?
A reaction goes faster when the
temperature is raised
Oh dear!
The Oven was too hot…
Reaction Rate – changing the rate
Lets make a graph
Reaction Rate – changing the rate
A rate of reaction increases when the surface area of a
solid reactant is increased
Reaction Rate – changing the rate
What is a catalyst?
Substance that increases the rate of a chemical
reaction, but remains chemically unchanged
itself
Reaction Rate – changing the rate
Manganese (IV) oxide acts as a catalyst for the reaction.
Why is that “Raw liver” acts as a catalyst to? ENZYMES!!!!!
Reaction Rate – changing the rate
Reaction Rate – collision theory
Do not Forget to relate the reaction rate with the
particle collision theory…
• The particles collide with each other
• The collision must have enough energy to be successful. In other
words, enough energy to break bonds to allow reaction to occur.
COLLISION THEORY
The rate of reaction depends on how many successful collisions there are in
a given unit of time.
Reaction Rate – explained by collision theory
Changing the reactant concentration
Reaction Rate – changing the rate
Changing the temperature
Reaction Rate – changing the rate
Reaction Rate – changing the rate
Reaction Rate – changing the rate
Reaction Rate – changing the rate
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