Factors affecting rates of reaction Flashcards
How does temperature affect the rate of reaction?
When the temperature is increased the particles move faster.
if they move faster they collide more frequently, because they move faster the more energy they have so more of the collisions have enough energy to make the reaction happen – increases rate of reaction
How can concentration or pressure affect the rate?
increases the rate of reaction
if a solution is more concentrated,it means there are more particles knocking about in the same volume of water.
Similarly, when the pressure of the gas increases, it means there are same number of particle occupying a smaller space
this makes collisions between reactant particles more freq
How can Surface area affect the rate of reaction?
If one of the reactants is a solid then breaking it up into smaller pieces increases its SA to volume ratio , this means for same volume of the solid the particles around it will have more area to work on = collisions more freq
How can catalysts affect the rate of reaction?
A catalyst is a substance which speeds up a reaction without being used up in the reaction itself.This means it’s not a part of the overall reaction equation.
Diff catalysts are used for different reactions but they all work by decreasing the activation energy needed to make the reaction occur.They do this by providing an alternate reaction pathway with a lower activation energy.
Enzymes are biological catalyst - they catalyse reactions in living things
