COLLISION THEORY
Collision theory says that the rate of reaction depends on the amount of collisions and how hard the particles collide. The harder the collisions and the more of them the faster the rate of reaction.
Temperature – More energy of the particles therefore more whizzing around and more collisions.
Higher concentration – (in a liquid) – More particles of reactant therefore more particles to collide with. (In a gas) it means there are more particles squished together therefore more collisions.
Larger surface area – more surface to collide with therefore more collisions
Activation energy – the amount of energy required for a reaction to happen
Catalyst – something that speeds up the reaction without being used up or changed in the reaction.
Solid catalyst – provides a surface for the particles to stick to therefore increasing the amount of collisions.
In industry:
- They allow you to increase the speed of production – plant doesn’t have to operate as long to produce the same amount of product (reducing costs)
- They allow reactions to happen at lower temperatures therefore less energy needs to be used in the reaction. This reduces costs and the environmental impact.
- The catalyst can be very expensive to buy and often have to be cleaned out of the product because they are mixed in – however they can be used over and over again because they aren’t used up in the reaction
- Different reactions need different catalysts – so you are going to need a lot of them if you make more than one product
- Catalysts can be poisoned by impurities and can stop working