Rates of Reaction Flashcards
example of a slow chemical reaction
rusting of iron
chemical weathering
on a rate of reaction graph, the steeper the line…
the faster the reaction
what is collision theory
the rate of a chemical reaction depends on:
how often the particles collide, the more collisions, the faster the reaction
the energy transferred during a collision, have to have enough energy to be successful
what is activation energy
the minimum amount of energy needed for a reaction to take place
what four things change the rate of reaction
temperature
concentration/pressure
surface area
cataylst presence
how does increasing temperature change the rate of reaction
particles move faster so more collisions occur
move faster=have more energy so collisions are more successful
how does increasing the concentration or pressure increase the rate of reaction
more particles in same volume means more collisions
how does increasing the surface area change the rate of reaction
for the same volume of solid, particles will have more area to collide with
how does using a catalyst affect the rate of reaction
decreases the amount of activation energy needed for the reaction to occur, so it is faster
what is catalyst
speeds up a reaction without being used up
formula for rate of reaction
amount of reactant used or amount of product formed
divided by
time
how to record rate of reaction by looking at precipitation and colour change
observe a mark through a solution and measure how long it takes for it to disappear
results are subjective, different people may not agree that the mark has gone or the solution has complelety changed colour
how to measure rate of reaction through change in mass
measuring the speed of a reaction that produces a gas, the gas will be released to the measurement on the balance will decrease, the faster this happens the quicker the rate of reaction
this is the best method as a balance is very accurate
how to measure rate of reaction by measuring the volume of gas given off
use a gas syringe to see how much gas goes into it in a set time, then calculate the rate of reaction.
what are the three methods of measuring change in rate of reaction
measuring precipitation and colour change
measuring a change in mass
measuring the volume of gas given off
