1. Chapter 16
Heat and Temperature

2. Temperature is a measure of how hot (or cold) something is compared to a reference point

3. Specifically, temperature is a measure of the average kinetic energy of the particles in an object due to their motions through space

4. Thermal Energy
Depends on the mass, temperature and phase (solid, liquid, gas) of an object

5. Thermal contraction
Slower particles collide less often and exert less force

6. Thermal expansion
Occurs when particles of matter move farther apart as
temperature increases-gases expand more than liquids and liquids expand more than solids

7. Thermal expansion is based on the attraction among the particles in the substance
Glass thermometers are based on this principle
As the temperature rises, the alcohol expands

8. Thermometer
Anything that changes in a measurable & predictable way when temperature changes

9. Temperatures can be expressed using different scales, for example: Fahrenheit
Celsius
Kelvin
The same temperature has different readings on each scales.

11. Different temperature scales are used for different purposes
Fahrenheit is used in the US for meteorology and in medicine
Celsius is used in science & for non-science in the rest of the world
Kelvin is used in physics, chemistry & astronomy

12. Absolute zero – the coldest possible temperature
molecular energy is at a minimum
when the volume of an ideal gas becomes zero C

13. Heat is energy transfer between objects that are different temperatures
Energy is always transferred from higher-temperature objects to lower- temperature objects until both objects are at the same temperature