rates of reaction Flashcards
what is collision theory
for a chemical reaction
- reactant particles must collide with each other
- particles must have enough energy to react
what is the rate of reaction
a measure of how quickly a reactant is used up
what is a successful collision
a collision that produces a reaction
what is activation energy
minimum amount of energy needed for a collision to be successful
how to calculate mean rate of reaction
quantity of reactant used / time taken
unit for rate of reaction
grams/second
mol/second
what happens when frequency of collisions increases
frequency of successful collisions also increases
what happens when a large lump is divided
volume stays the same
area increases
sa:vol ratio increases
what happens when temperature increases in a reaction
- particles move quicker
- energy increases
- frequency of particles increases
- proportion of collisions which are successful increases
- rate of reaction increaes
what does a catalyst do
provides an alternative reaction pathway that has a lower activation energy
how can you tell when a reaction is complete
when no more gas is produced and line on graph is horizontal
how to describe a curve on a graph for tempreature
greater the temperature the greater the reaction rate, rate increases by a greater amount at higher temperatures
