c8 Flashcards
what is rate of reaction
measures the speed of a reaction.
how can you workout the rate of a chemical reaction
find out how quickly the reactants are used up and the product of the reaction is made
how can you find how quickly the reactants are used up
by measuring the mass of a reaction mixture and measure and time intervals
how can you find the rate of a reaction from a graph
found from the gradient
what is the equation for mean rate of reaction
quantity of reactant used (product formed) / time taken
what is collision theory
states that reactions can only happen if particles collide and collide with enough energy to change into new substances
how can you increase the rate of reaction
increase the frequency of particles colliding with eachother
increase the energy they have when they collide
what factors will increase the rate of reaction
increasing temperature
increasing concentration of reactants
pressure of reacting gases
increase surface area of solid
use of catalysts
how does increasing surface area increase rate of reaction
breaking large pieces of solid into smaller pieces exposes new surfaces which means there are more collisions at the same time.
how does temperature increase rate of reaction
increases particle energy so they collide more often and with more energy
how does increasing the concentration of reactants increases rate of reaction
there are more particles of the reactants moving around in the same volume of solution which increases the likelihood of collisions
how does an increase in pressure of gases increase rate of reaction
increasing pressure squashes the particles closer together so there are more particles in less space increasing the likelihood they collide
what is a catalyst
changes the rate of reaction
how does a catalyst increase rate of reaction
provides a different pathway to the products with a lower activation energy.
why can catalysts be used over and over again
a catalyst is not used up or changed chemically in a reaction
