C2.4 Rates and Energy Flashcards
What is activation energy?
The smallest amount of energy needed to start a reaction.
Define collision theory.
When reacting particles collide with enough energy for a chemical reaction to take place.
What is the rate of reaction?
It is how quickly a reaction takes place.
Why does the rate of reaction increase when the surface area increases?
There are more surfaces for collisions to happen against so more reactions take place.
How does heat affect the rate of reaction?
If the temperature is higher,the rate of reaction will be higher.
What does the Haber Process produce?
Ammonia
What is reacted in the Haber Process?
Hydrogen and nitrogen
What are the ideal conditions for the Haber Process?
With an iron catalyst.
A high temperature of around 450 degrees celsius.
High pressure- around 200 atmospheres
How does a catalyst affect the rate of reaction?
A catalyst increases the rate of reaction.
Why are catalysts useful to chemical production companies?
They speed up reactions so chemicals can be produced quicker and can be used multiple times.
What does exothermic mean?
Energy is being transferred from the reactants to the surroundings.
Heat is given off
What does endothermic mean?
Energy is being transferred from the surroundings to the reactants.
Heat is taken in
State a positive for using catalysts.
They speed up a reaction.
Only a small amount is needed to speed up a reaction.
State a negative for using catalysts.
They are often expensive.
They eventually become ‘poisoned’ by impurities and stop working.
How do we calculate rate of reaction?
Amount of reactant used / time
Amount of product formed / time
