Chapter 3

1. Chapter 3 Maria Isabel futch Maria Isabel Bandes Alexandra quinonez Rosa Kawas

2. States of matter Section 1

3. SOLIDS • A solid has a definite shape and a definite volume no matter where you put it or how you use it. For example if your notebook has a rectangular shape and your pen has a volume of 6 cubic centimeters they will keep that shape and volume in any position or in any container.  The particles in a solid are very close together, each particle is fixed in one position. This causes a solid to have a definite shape and a definite volume. Although the particles in a solid are not completely motionless they do vibrate back and forth but they always stay in the same position

4. Types of solids • Crystalline: In some solids the particles form a regular repeating pattern. These patterns create solids made up of crystals which are called crystalline solids. Salt, sugar and snow are examples of crystalline solids. When a crystalline solid is heated, it melts at a specific temperature. • Amorphous: In amorphous solids, particles are not arranged in a pattern. Plastic, rubber and glass are examples of amorphous solids. Unlike a crystalline solid an amorphous solid does not melt at a specific temperature. Instead it may become softer or change into other substances.  

5. Liquids •  A liquid has a definite volume but not a definite shape. If you tried to squeeze a plastic bag full of water, the water may change shape but the volume will not in increase or decrease. • The particles in a liquid are packed almost as closely as in a solid, but they move around one another freely. Because liquid particles are free to move, a liquid has no definite shape. However it does have a definite volume. These freely moving particles allow a liquid to flow from place to place, that why it is also called a fluid, meaning “a substance that flows.”

6. Gas • It can change volume very easily. The particles in a gas can move freely. What determines the volume of a gas is the volume of the container it is in. As the particles move they spread apart , filling the space available. That is a why a gas has no definite shape neither volume.

7. Solids, liquids, and gases

8. Changes of state Section 2

9. Melting • A change from solid to liquid involves an increase in thermal energy. A change from liquid to solid involves the opposite, a decrease in thermal energy. • Melting: the change in state from a solid to a liquid, melting occurs at a specific temperature called the melting point.

10. Vaporization • The change from a liquid to a gas is called vaporization. Vaporization takes place when the particles in a liquid gain enough energy to form a gas. Vaporization that takes place only on the surface of a liquid is called evaporation. Another kind of vaporization is called boiling. Boiling occurs when a liquid changes to a gas below its surface as well as at the surface. The temperature at which a liquid boils is called its boiling point.

11. Freezing… • The change of state from liquid to solid is called freezing. It is the reverse of melting. At its freezing temperature, the particles in a liquid are moving so slowly that they begin to form regular patterns. When you put water into a freezer, the water loses energy to the cold air in the freezer. The water molecules move more and more slowly as they loose energy. As time passes, the water becomes solid ice.

12. Condensation • Condensation is the opposite of evaporation. Condensation occurs when the particles in a gas loose enough thermal energy to form a liquid. You can observe condensation by breathing on to a mirror, when warm water vapor reaches the surface of the mirror, the water vapor condenses into drops of liquid.

13. Sublimation… • Sublimation occurs when the surface particles of a solid gain enough energy that they from a gas. During sublimation, particles of a solid do no pass through the liquid state as they form a gas. One example of sublimation is dry ice. Dry ice is the common name for solid carbon dioxide. Carbon dioxide cannot exist as a liquid so instead of melting, solid carbon dioxide changes directly into a gas. While it is changing, the dry ice absorbs thermal energy. When dry ice becomes a gas, it cools water vapor in the nearby air. The water vapor then condenses into a liquid, forming fog around the dry ice.

14. Melting vaporization Solid Gas Liquid Boiling Point Melting Point Condensation Freezing Sublimation Deposition

15. Section 3 Gas Behavior

16. Pressure and Volume • This relationship can also be know as boyles law. The variables pressure and volume vary inversely to each other. When pressure increases volume decreases, when pressure decreases, volume increases.

17. PRESSURE AND TEMPERATURE • Whenthetemperature of a gas isincreasing, thepressuredecreases. Thenwhenthetemperature of a gas decreasesthepressureincreases. Forexamplethehigherthetemperature of a substancethefasteritsparticles are moving. • In a 18-wheel truck tire as thetemperatureincreases so doesthepressure of the air insidethe tire. Ifthepressurebecomesgreater, thenthe tire can hold more, forthisreasontruckdirversneedtoadjust and monitor tires in longtrips.

18. Temperature and Volume • This can also be called Charles law. The variables are directly proportional with each other. When temperature increases volume increases, and when temperature decreases volume decreases.

19. Section 4 Graphing Gas Behavior

20. Temperature and Volume • This can also be called Charles law. The variables are directly proportional with each other. When temperature increases volume increases, and when temperature decreases volume decreases.

21. Pressure and Volume • This relationship can also be know as boyles law. The variables pressure and volume vary inversely to each other. When pressure increases volume decreases, when pressure decreases, volume increases.