Reactions Flashcards
What can increase the rate of reaction?
- surface area
- temperature
- concentration
- catalysts
How does surface area increase the rate of reaction?
More surface particles = more collisions
How does temperature increase rate of reaction?
Higher temperatures = more energy
More energy = move movement / more successful collisions / more likely to have the activation energy
How does concentration increase the rate of reaction?
Higher concentration = more particles in a given space = more successful collisions / closer together resulting in more successful collisions meaning more likely to have the activation energy
How does a catalyst increase the rate of reaction?
It provides a surface which particles can collide on, this reduces the activation energy
They also bring the particles together to collide
What is the rate of reaction?
The rate in which the reactants make up the products
What is an exothermic reaction?
One which transfers heat energy to its surroundings due to bonds being broken / made
What are some examples of exothermic reactions?
Combustion
Respiration
Neutralisation reactions
What is an endothermic reaction?
One which takes energy from its surroundings such as thermal decomposition
What are the energy transfers like in reversible reactions?
Equal but opposite (eg endothermic in one direction, exothermic in the other)
What can exothermic reactions be used to do?
Heat things up
What can endothermic reactions be used to do?
Cool things down
Why are catalysts economical?
They are expensive however do not need replacing often
Why can some catalysts be toxic?
Because some of them and their compounds involve transition metals
What makes catalysts as effective as possible?
Their surface area
