Bonds and energy changes Flashcards
What happens during a chemical reaction
Bonds between atoms and a reactant are broken, and new bonds between atoms and the products are formed
What needs to happen for energy to break bonds
Energy needs to be taken in, therefore it is an endothermic reaction
What needs to happen for energy to make bonds
Energy must be released to the surroundings, therefore it is an exothermic reaction
What are bond energies
The amount of energy required to break the bond or the amount of energy given out when the bond is formed
What can bond energies be used to determine
Overall energy change for the reaction
If more energy is released than absorbed
The reaction is exothermic
Is energy change negative or positive for exothermic reactions
Negative
If more energy is absorbed than released
The reaction is endothermic
Is energy change negative or positive for endothermic reactions
Positive
