- Internal energy is the sum of temperature (ke) and phase (pe) conditions.
- Steam and liquid water molecules at 100 degrees have equal kinetic energies.
- Degrees Kelvin (absolute temp.) Is equal to zero (0) degrees Celsius.
- Temperature measures the average kinetic energy of the molecules.
- Phase changes are due to potential energy changes.
- Internal energy always flows from an object at higher temperature to one of lower temperature.