1. Intro to chemistry Therm o breaking forming
A. All chemical reactions involve the ________ and ________ of bonds.
breaking
forming

2. Intro to chemistry Therm o sum endothermic absorbed
1. The energy required to break all of the reactant bonds is a ______ of all of the average bond energies in the reactants. This is an ___________ term. Energy must be ________ in order to break bonds!
sum
endothermic
absorbed

3. Intro to chemistry
Therm o
2. The energy released in making all of the product bonds is a ______ of all of the average bond energies in the products. This is an _________ term. Energy is _______ when new bonds form!
sum
exothermic
released

4. Intro to chemistry Therm o Overall enthalpy
3. The ________ enthalpy change in a reaction relates the bond breaking (endothermic) process and the bond making (exothermic) process. The total _________ change can be negative (exothermic) or positive (endothermic) depending on the relative magnitude of the two (breaking and making) processes.
enthalpy

5. ΔHrxn = Ʃn(ΔHbonds broken) - Ʃn(ΔHbonds formed)
Intro to chemistry
Therm o
The enthalpy change, ΔH, for a reaction can be calculated from a list of bond _______ and the following understanding:
ΔHrxn = Ʃn(ΔHbonds broken) - Ʃn(ΔHbonds formed)
energies

6. Intro to chemistry
Therm o