Rates Of Reaction Flashcards
1
Q
What 5 factors affect the rate of reaction?
A
- conc of reactants
- temperature
- surface area (solid only)
- catalysts
- intensity of radiation for reactions involving photodissociation
2
Q
How does increasing the concentration or pressure increase rate?
A
Reactant particles are closer together so collisions are more frequent (not all collisions result in a reaction, only collisions with enough energy to overcome the activation energy)
3
Q
Ways of measuring/following the concentration of a reaction
A
- measure volume of gas produced
- measure mass lost (for open system reactions producing gas)
- remove measured volumes (using a pipette) at known time intervals & do a suitable titration
- colorimetery (measure colour change of solution with a colorimeter)
- pH change w/pH meter if conc of H+ changes
- conductivity meter if number of ions changes
4
Q
How does increasing temp increase rate of reaction?
A
- reacting particles have more KE so move faster and collide more frequently
- because particles move faster, a higher proportion of collisions will have a total energy at or above activation energy & will result in a reaction
5
Q
How do catalysts increase rate of reaction?
A
Provide alternative route for reaction that has a lower activation energy
6
Q
Draw maxwell-Boltzmann curve w/catalyst
A
.
7
Q
Draw maxwell-Boltzmann curve w/increases temp
A
.
8
Q
How do heterogeneous catalysts work?
A
- reactant molecules are adsorbed onto the catalyst surface which weakens bonds w/in reactant molecules
- bonds w/in reactant molecules break (takes less energy as bonds are weakened)
- new bonds form, making the product molecules
- product molecules leave the catalyst surface via desorption
9
Q
Draw a reaction profile for a homogeneous catalyst
A
.
