1. Topic: Heat and Temperature PSSA: 3.4.7.C / S8.C.2.1

2. Objective: TLW define temperature. TLW explain the role of thermal expansion in measuring temperature. TLW identify the boiling and freezing point of water in all three temperature scales. TLW convert temperatures into all three temperature scales.

3. MI #1: What is temperature? Temperature is the measure of the average kinetic energy of the particles in an object. This means that temperature is actually a measure of how fast the atoms or molecules of a substance are moving.

4. MI #2: Measuring Temperature Temperature is measured using a thermometer. Thermometers measure temperature because of thermal expansion. - the fluid inside the thermometer expands as it gets warmer so it takes up more room inside the thermometer. Most thermometers use alcohol, but mercury was a common thermometer liquid at one time.

5. MI #3: Fahrenheit Scale The Fahrenheit scale is the temperature scale used in the USA. Freezing Point of Water = 32° Boiling Point of Water = 212°

6. MI #4: Celsius Scale The Celsius (or Centigrade) Scale divides the difference between the freezing and boiling points of water into 100 equal parts (called degrees Celsius). Freezing Point of Water = 0° Boiling Point of Water = 100°

7. MI #5: Kelvin Scale The Kelvin scale uses the same increments as the Celsius scale, however it begins at absolute zero. Absolute zero is the temperature at which all molecular motion stops. Freezing Point of Water = 273 K Boiling Point of Water = 373 K There are no negative temperatures on the Kelvin scale.

8. MI #6: Temperature Conversions °C to °F: °F = (9/5 x °C) + 32 °F to °C: °C = 5/9 x (°F – 32) °C to K: K = °C + 273 K to °C: °C = K - 273

9. So What…? Real Life Application Measuring temperature accurately is an important skill in cooking, diagnosing illness, etc.