Paper 2- Kinetics Flashcards
(12 cards)
Define rate of reaction
The change in concentration of a substance in unit time
Why is the reaction fastest at the beginning?
Plenty of available reactant particles so successful collisions occur more frequently
Why does rate of reaction increase with concentration?
More particles in a given volume so more particles collide with energy greater than the activation energy
Define activation energy
Minimum energy particles must collide with for a reaction to take place
Why does increasing pressure increase rate of reaction?
More particles per given volume so more frequent collisions, meaning more particles collide with energy greater than the activation energy
Define dilute
Less particles per unit volume
Define concentrated
More particles per unit volume
Why does increasing temperature increase rate of reaction?
Moving faster so collide more frequently
Higher proportion will have energy greater than the activation energy
Why does increasing surface area increase rate of reaction?
More reactant particles available to react so more frequent collisions
What does the area under a Maxwell-Boltzman curve represent?
The total number of molecules
Define a catalyst
A substance which speeds up a chemical reaction without being used up
How does a catalyst increase the rate of reaction?
Provides an alternative pathway with a lower activation energy so a greater proportion of particles will have energy greater than the activation energy
