C8 - Rates And Equilibria Flashcards
Rate of reaction
Amount of reactant used / time
Amount of product formed / time
Factors affecting the rate of reaction
Surface area
Temperature
Concentration / pressure
Catalysts
Collision theory - surface area
When more of the surface area is exposed, there are more particles able to react = more collisions, and a faster reaction
Temperature
When particles are hotter, they have more energy, making a collision more likely
Concentration
The more concentrated the solution is, the faster the reaction
High concentration = more crowded particles, therefore more collisions
Pressure
When increasing the pressure we are squeezing the molecules closer together (making them more concentrated) = more collisions
Catalysts
Reduces the activation energy
Reversible reactions
Can go forwards and backwards
If the forward reaction is exothermic, the backward reaction will be endothermic, and vice versa
Dynamic equilibrium
When two opposite changes occur at the same time but there is no overall change in the system
Closed system
Contains a fixed amount of matter
A dynamic equilibrium can only exist within a closed system
