•even though Chemistry is the study of matter, energy effects matter
•energyis anything that has the capacity to do work
•workis a force acting over a distance
- Classification of Energy: Kinetic energy, Potential energy
- Law of Conservation of Energy:
•energy cannot be created or destroyed
First Law of Thermodynamics
•energy can be transferred between objects
•energy can be transformed from one form to another
heat → light → sound
- How Is Energy Exchanged?
•energy is exchanged between the system and surroundings through heat and work
q= heat (thermal) energy
w= work energy
q and w are NOT state functions, their value depends on the process
delta E= q + w
Measuring delta E, Calorimetryat Constant Volume
Measuring delta H, Calorimetryat Constant Pressure
- Relationships Involving delta Hrxn and Hess’s Law