Rates of Reaction and Energy Changes Flashcards
How to calculate the rate of reaction
The amount of reactant used / time
Examples of experiments that can be done to observe reaction rates
Precipitate
Change in mass
Volume of gas
How to increase the rate of reaction
Increase temperature
Increase concentration
Increase SA
What does a catalyst do
Speed up the rate of reaction without being used up by providing an alternate pathway with a lower activation energy
Example of biological catalysts
Enzymes
What is an exothermic reaction
One that gives out energy to the surroundings, usually in the form of heat
What is an endothermic reaction
One that takes in energy to the surroundings, usually in the form of heat
What does an endothermic reaction profile look like
Products higher than reactants
What does an exothermic reaction profile look like
Products lower than reactants
What is activation energy
The minimum amount of energy required for bonds to break and the reaction to begin
Are most neutralisation reactions endo or exo thermic
Exo
Are most displacement reactions endo or exo thermic
Exo
Are most precipitation reactions endo or exo thermic
Exo
How to work out overall energy change using bond energies
Energy required to break bonds - energy released to form bonds
If it is negative then the (forward) reaction is exothermic
