Energy Changes Flashcards
What is an exothermic reaction?
A reaction where energy is transferred to the surroundings
Give three common examples of exothermic reactions
Combustion, neutralisation and most oxidation reactions
Give two uses of exothermic reactions
Hand warmers and self heating cans
What is an endothermic reaction?
A reaction where energy is taken in from the surroundings
Give two examples of endothermic reactions
The reaction between citric acid and sodium hydrocarbonate and thermal decomposition
Give a use of endothermic reactions
Sports injury cooling packs
What is the activation energy on a graph?
The initial rise in energy needed to start the reaction
Why is the activation energy needed?
It allows the reactants to collide together and react, starting the reaction
Out of bond breaking and bond making, which is endothermic and which is exothermic?
Bond breaking is endothermic (energy must be supplied) and bond making is exothermic energy is released)
