1. Temperature (Sect. 8.2)  There are two common temperature scales: Fahrenheit scale Fahrenheit scale ○ Water freezes at 32º and boils at 212º Celsius scale Celsius scale ○ Water freezes at 0º and boils at 100º Jennifer C. Brown

3. Temperature (Sect. 8.2)  What is Temperature? Atoms are in constant motion, even in a solid object. The back-and-forth jiggling of atoms is caused by thermal energy, which is a kind of kinetic energy. Jennifer C. Brown http://www.epa.gov/apti/bces/module1/kinetics/animation/kani1/kani104.htm

4. Jennifer C. Brown

5. Temperature (Sect. 8.2)  Temperature measures the kinetic energy per molecule due to random motion.  Average motion leads to a speed. Random motion leads to a temp. Jennifer C. Brown

6.  A thermometer is an instrument that measures the exact temperature.  Most thermometers contain either a silvery fluid (mercury) or a red fluid, which is alcohol containing a small amount of red dye.  How do they work? Temperature (Sect. 8.2) Jennifer C. Brown

7. Temperature (Sect. 8.2)  Absolute Zero? = -273ºC = 0 K Uses the Kelvin (K) Scale Uses the Kelvin (K) Scale You cannot have a temperature lower than absolute zero. Think of absolute zero as the temperature at which atoms are “frozen.” Jennifer C. Brown To convert from Celsius scale to Kelvin scale, you just add 273 to your Celsius temperature.