Endothermic and Exothermic Reactions

• chemical reactions that involve a change in energy
• held together by chemical bonds
• bonds are broken by adding energy
• energy is needed to have bonds join together

2 types: endothermic and exothermic

endothermic:

• absorbs energy 

exothermic:

• releases energy

Enthalpy H is H product - H reactant. It is the heat contained in the system.

Energy Diagrams:

• Activation energy is the energy needed to be added in order for the reaction to progress.
• Delta H is the change in enthalpy: energy of products - energy of reactants.