Energy in chemical reactions

Heat

Exothermic

An exothermic reaction is one that gives out heat

Exo (exit)

Thermic (themperature)

Endothermic

An endothermic reaction is one that takes in heat

Collision Theory

When a chemical reaction occurs, certain energy changes must take place

For the reaction to occur, the particles of the reactants must collide with each other to produce a product, they can only do this is a certain minimum energy is reached during the collision

This is called effective collision

Effective collision: a collision that results in the formation of products

Activation energy: minimum amount of energy needed for an effective collision to occur

Energy profile diagram

An energy profile diagram is a graph that shows a change in energy of a chemical reaction with time as the reaction takes place

x-axis: time

y-axis: change in energy