Reactions Flashcards
what is collision theory?
for a particle to react, they have to collide with each other with sufficient energy 
what is activation energy?
The minimum energy required for bonds to break
How does temperature impact rate of reaction?
increase in temperature Makes the particles gain more thermal energy
make them move faster
colliding more frequently and colliding with more energy
Higher rate of successful collisions
How does concentration and pressure affect rate of reaction?
The more particles per unit of volume makes the collisions more frequent
increasing the rate of reaction
how does surface area affect rate of reaction?
The larger, the surface area, the increase rate of reaction
Increase in more frequent collisions
what has a larger surface area powder, solid, blocks or chunks?
Powder has the highest surface area to volume ratio, which increases frequency of collisions
What do catalysts do to reactions?
lowers activation energy by providing an alternative reaction pathway, giving a higher proportion of successful collisions 
What happens in the exothermic reaction and some examples?
Energy is released to surroundings via heat
Combustion and neutralisation are examples of exothermic reactions
what happens in endothermic reactions and examples of them?
Takes in heat from the surroundings
Photosynthesis, ice melting and alkane cracking examples of endothermic reactions
what start of higher in a reaction profile for exothermic reactions
It goes from reactants to products
What starts of lower in an endothermic reaction profile?
reactants start of lower in a reaction profile, as energy is absorbed, forming products

Is Bond breaking endothermic or exothermic?
Bond breaking is endothermic as it requires energy from the surroundings to break bonds
is bond, forming, exothermic or endothermic
it is exothermic as it releases energy to surroundings to form bonds
is bond, forming, exothermic or endothermic
it is exothermic as it releases energy to surroundings to form bonds
what is bond energy
Amount of energy required to break one mole of a bond
How do you calculate overall energy change?
Energy required to break bond - energy released by forming bonds 
if overall energy change is negative negative what type of reaction is it?
It is an exothermic reaction as there is a loss of energy
How do you investigate rate of reaction?
Disappearing, cross reaction, experiment
how do you do a disappearing cross experiment?
Draw cross on white tile place floss over it add sodium thiosulphate to it and then add in a small volume of hydrochloric acid and time how long it takes for the cross to disappear
Faster cross disappears =
= Higher rate of reaction
how do you calculate rate of reaction
rate =1/time
