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Rate of reaction - Coggle Diagram

- - - - The reaction is in a sealed container (closed system)
      - The rate of forward reaction = rate of reverse reaction
  - - - Adding or removing reactants or products
      - Changing the pressure
      - Changing the temperature
  - - - Pressure 200atm
        
        Needs high pressure to increase yield of ammonia but not too high for safety reasons
      - Temperature 450 degrees celcius
        
        Need low temperature to increase yield of ammonia but high temperature to increase rate of reaction
      - Fe catalyst
        
        Increases rate, allowing a lower temperature to be used
    - - Forward is exothermic
      - Reverse is endothermic
- - - - Cost-effective
        
        Despite the fact catalysts are expensive precious metals they are often cost effective as
        
        A small amount can speed up a reaction by a lot
        
        Paying for catalysts may be cheaper than paying for the energy to increase temperature or pressure
      - Reducing burning of fossil fuels
        
        By reducing temperatures or pressures needed fewer fossil fuels are burned meaning negative environmental impact is reduced
    - - Toxicity
- - - - Yield more product in a given amount of time
      - However, it may be expensive to generate conditions for fast reactions and safety drawbacks associated with fast reactions
- - - - This minimum amount of energy required is known as the activation energy
    - - We can increase the rate of a reaction by increasing the frequency of collisions and the energy of reactant particles
      - This can be achieved by changing different factors:
        
        Increasing concentration of reactants increases the collision frequency and therefore rate of reaction (in dissolved reactants)
        
        Increasing pressure increases the collision frequency and therefore the rate of reaction (in gaseous reactants)
        
        Temperature increases rate which collisions happen
        
        Increasing temperature increases energy of reactant particles meaning more particles will have energy greater than the activation energy required
        
        Both of these factors lead to more successful collisions and therefore the rate of reaction increases with the temperature
        
        Increasing surface area increases collision frequency and therefore rate of reaction
        
        Catalysts
        
        Reduce activation energy required for particles through an alternate reaction pathway