Ch. 2: States of Matter

1. Ch. 2: States of Matter

2. Section 1:Three States of Matter

3. Three States of Matter • States of matter - the physical forms of matter, which include solids, liquids, and gases. • Matter is made up of tiny particles called atoms and molecules, which are always in motion and always bumping into one other.

4. (((( )))) (((( )))) (((( )))) (((( )))) Solids • Solids have a definite shape and volume. • Particles are very close together • Particles are locked in place • Only movement is vibration

5. Types of Solids • Crystalline solids have a very orderly, three-dimensional arrangement of particles. e.g., iron, diamond, ice

6. Types of Solids • Amorphous solids are made of particles that do not have a special arrangement. e.g., glass, rubber, wax

7. Liquids • Liquids - have a definite volume but not a definite shape. - Take the shape of their container. - Particles move fast enough to overcome some of the attractions between them. - Particles slide past each other

8. Surface Tension • Surface tension - the force that acts on the surface of a liquid and that tends to minimize the area of the surface. Water Strider

9. Viscosity • Viscosity - a liquid’s resistance to flow. • Caused by the attraction between molecules of a liquid.

10. Viscosity • Viscosity - a liquid’s resistance to flow. • Caused by the attraction between molecules of a liquid. Which has a higher viscosity? Water Motor Oil

11. Gases • Gases - do not have a definite volume or shape. • Takes the shape and volume of container • Particles move quickly • Less attraction between particles

12. States of Matter Solids, Liquids, and Gases Link

13. Section 2:Behavior of Gases

14. Respond in your notebook: How do you think a railroad tank carlike this, which is made out of 7/16” steel…

15. …turned into this?

16. Behavior of Gases • Temperature - a measure of how fast the particles in an object are moving. • Faster particles have more energy and push with a greater force • Gas Properties Simulator

17. Behavior of Gases • Volume - the amount of space an object takes up. volume of a gas = volume of its container

18. Behavior of Gases • Pressure - the force exerted on a given area of surface. - collisions of gas particles with their container

19. Gas Laws • Boyle’s Law - the volume of a gas is inversely proportional to its pressure.  pressure =  volume  pressure =  volume

20. Boyle’s Law

21. Charles’s Law • Charles’s Law - the volume of a gas is directly proportional to its temperature. •  temperature =  volume •  temperature =  volume

22. Charles’s Law

23. Section 3:Changes of State

24. Changes of State • Change of state - the change of a substance from one physical form to another. • Identity of the substance does not change • Energy must be added or removed

25. Melting • Melting - the change of state from a solid to a liquid. • As the temp. , particles move faster

26. Melting • Melting point - the temp. at which a substance changes from a solid to a liquid. • - different for each substance • Melting Points • water 0°C gallium 30°C table salt 801°C

27. Adding Energy • Melting is an endothermic change - it absorbs heat energy. (Heat energy must be added.) • When an object is at its melting point, heat energy is used to overcome the attractions that hold the particles in place.

28. Freezing • Freezing - the change of state from a liquid to a solid. • -As the temp. , particles slow down

29. Freezing Point • Freezing point - the temp. at which a liquid changes into a solid. • An object’s freezing point = its melting point

30. Removing Energy • Freezing is an exothermic change - it releases heat. (Heat energy must be removed.) • For an object to freeze, the attractions between the particles must overcome the motion of the particles (the particles slow down as they lose energy).

31. Evaporation • Evaporation - the change of a liquid to a gas. • - Can occur below the boiling point at the • surface of a liquid • - Water absorbs energy from its surroundings • to escape into a gas

32. Boiling • Boiling - the change of a liquid to a vapor throughout the liquid. • - Occurs when the vapor pressure (inside the bubbles) equals the atmospheric pressure (outside of the bubbles). • - Endothermic

33. Boiling • Boilingpoint - the temperature at which a liquid boils. • - Doesn’t change with the amount of the • substance Boiling point of water = 100°C

34. Boiling • Atmospheric pressure affects a substance’s boiling point. • At higher elevations, there are less air particles pushing down, so liquids can more easily escape as gases.

35.  atmospheric pressure =  boiling point •  atmospheric pressure =  boiling point

36. Boiling Boiling point of water = 95°C A liquid can’t get any hotter than its boiling point! Boiling point of water = 100°C

37. Condensation • Condensation- change of a gas to a liquid. • - Large numbers of particles clump together • when the attraction between them overcomes • their motion. • - Exothermic (energy • is removed which • slows down the • particles)

38. Condensation • Condensationpoint- temperature at which a gas becomes a liquid. • condensation point = boiling point

39. Sublimation • Sublimation - change of a solid directly to a gas. • - Particles move from being very tightly packed to being spread far apart. • - Endothermic

40. Change of Temperature vs. Change of State • When most substances gain or lose energy, either their temperature will change or their state will change. • Both do not happen at the same time. • YouTube - Changes of State

41. Changing the State of Water