2. Chapter 6

3.  All matter is made up of atoms or molecules.  These particles are constantly in motion. The energy of motion is called kinetic energy.  Temperature is the measure of the average Kinetic Energy of the individual particles in a substance.

4.  Whenever something becomes warmer, the kinetic energy of its atoms or molecules has increased. The temperature of the hot liquid has increased.

5.  Particles in the cold chocolate milk are moving slower than the hot chocolate and the particles have a lower temperature or kinetic energy.

6.  A thermometer is used for measuring temperature.  As the liquid in the thermometer becomes warmer, the molecules move faster and further apart, and the liquid in the tube rises.  As the liquid cools, the molecules move slowly and the liquid contracts in the tube.

7.  The 3 most common scales for measuring temperature are the Fahrenheit, Celsius, and Kelvin Scales

8.  The temperature scale used commonly in the United States is the Fahrenheit scale.  The number 32 is the temperature at which water freezes.  The number 212 is the temperature at which water boils  The interval between these two temperatures is divided between 180 equal intervals called degrees Fahrenheit

9.  The most widely used temperature scale in the world is the Celsius scale.  The number 0 is the temperature at which water freezes.  The number 100 is the temperature at which water boils.  The interval between freezing and boiling is divided into 100 equal parts, called degrees Celsius.

10.  The temperature scale used in Physical Science is the Kelvin Scale.  Units on the Kelvin Scale are the same size as the Celsius Scale and are called kelvins (K)  Freezing Point of water on the Kelvin Scale is 273 K and the Boiling Point is 373 K

11.  Scientists believe that -273 degrees Celsius or 0 degrees Kelvin is the lowest temperature possible.  At this temperature no more energy can be removed from the matter.  This temperature has not truly been reached.

12.  The total energy of all the particles in a substance is called the Thermal Energy or Internal Energy  If two samples of matter have the same temperature does not mean that they have the same Energy.

13.  The more particles a substance has at the given temperature the more the more thermal energy it has  The water in the bucket has greater Thermal energy than the cup of water at the same temperature. Thermal Energy is the measure of the energy of all the particles.

14.  What is the relationship between the temperatures of a substance and the speed of its molecules?

15.  The higher the temperature of a substance, the faster is the motion of its molecules

16.  Power point Compiled by Mrs. Lal for 8 Z Students  Text Book “ Science Explorer” by Prentice Hall