Effect Of Temp On Rate Flashcards
How to determine the rate of a chemical reaction
By the frequency of successful collisions
Effect of increasing the temperature
Increase the rate of reactions
= as it would increase the energy of particles
= means they will move faster
= increases frequency of collisions
Each collision has more energy
= more particles can overcome activation energy barrier and collide successfully
Importance of catalysts
Allow us to carry out reactions quickly without needing to increase temp
= saves money
Can reuse them as not used up
How do catalysts affect the rate
Increase rate by providing a different pathway for the reaction that has a lower activation energy
Why don’t we include catalysts in the chemical equation for a reaction
- they aren’t used up in the reaction as they aren’t a reactant
- different reactions need different catalysts
- enzymes act as catalysts in living organisms
How to change direction of reversible reactions
By changing the conditions
Describe copper sulphate reactions
- produces white sulphate and water
- energy is being put into it
= forward reaction is endothermic - if water added back reaction reverses
= exothermic
Define an equilibrium
The forward and reverse reactions will take place at exactly the same rate
Effect of changing conditions on equilibrium
The reaction responds to counteract the change
How does pressure affect reversible reactions
The position of equilibrium shifts to the side with the smaller number of molecules
What happens if pressure is reduced to a reversible reaction
The position of equilibrium shifts to the side with the larger number of molecules
Effect ps large surface area to volume ratio
More particles on surface
= more collision per second
= increases rate of reaction
How do catalysts speed up reaction
Provides different reaction pathway which has lower activation energy
