Summary Into to chemistry energy

EnergyChapter 10

Energy
- Ability to do work or heat
- Energy cannot be converted from one form to another; but cannot be created or
destroyed
- Different type of energy
o Potential energy – energy due to position or composition
o Kinetic energy – due to motion
- Temperature
o A measure of the random motions of the components of a substance
- Heat
o A flow of energy between two objects due to temperature
difference between the objects
 Heat is a way in which thermal energy is transferred from
a hot object to a colder object
- System
o Part of the universe on which we wish to focus attention
- Surroundings
o Including everything in the universe

Endothermic process
- Heat flow is into a system
- Absorb heat (energy) from the surrounding
o Example: watering boils in a kettle being heated on a stove

Exothermic process
- Energy flows out of the system; Release heat
o Example: Your hand gets cold when you touch ice

*Energy gained by the surroundings must be equal to the energy lost by the system*

Units
The common energy units for heat are the Calorie and the joule
Calorie: the amount of energy required to raise the temperature of one gram of water 1
degree

Joule: 1 calorie = 4.184 joules