C8 - rates and equilibrium Flashcards
Why do reactions get slower over time
Higher concentration of products and lower concentration of reactants so reactants less likely to collide
What conditions need to be met for particles to react when they collide
Correct orientation and activation (minimum) energy
What 4 things increase the rate of reaction
Increasing temperature, surface area of reactants, concentration, or adding a catalyst
What do catalysts do
Provide an alternate pathway for reaction with a lower activation energy
How do catalysts work
On the surface of the catalyst, the reactants bond to the catalyst weakening their own bonds, so when they collide they are more likely to break and react
What system must it be for an equilibrium to be reached with a reversible reaction
Closed
If the forwards reaction is exothermic, what is the backwards reaction
Endothermic
What is a dynamic equilibrium
When the forwards and backwards reaction are happening at the same rate
How do you increase the percentage yield from a reversible reaction
Change the conditions to favour the forwards reaction and remove the products when they are formed so it doesn’t form a dynamic equilibrium
What effect does increasing concentration of one substance have on a reversible reaction
Moves the reaction towards the other substance
What effect does increasing the temperature have on a reversible reaction
Favours the endothermic reaction
What effect does increasing pressure have on a reversible reaction
Favours the side with less molecules
What do you have to do when choosing conditions for a reversible reaction
COMPROMISE
