Pretest

1. Pretest Chapter 3 1. What is the density of a sample whose mass is 12.02 g and whose volume is 6.01 mL? 2. Which of the following is an element? a. sandb. waterc. goldd. sugar 3. Differentiate heterogeneous from homogenous mixtures.

2. Pretest (continued) Chapter 3 4. Which of the following is NOT a step in a valid scientific method? a. developing a procedure to test your hypothesis b. drawing a conclusion without any supporting evidence c. forming a testable hypothesis d. making observations 5. Identify the tools needed to measure temperature and length. 6. True or False: All of the following units are SI units: meter, pound, and Kelvin.

3. Pretest (continued) Chapter 3 7. Density, mass, and volume are related by the equation density = mass/volume. What equation would you use to find volume if you knew the density and mass? 8. Bromine boils at a temperature of 58.63˚C. What is this temperature in Kelvin?

4. Pretest Answers Chapter 3 1. What is the density of a sample whose mass is 12.02 g and whose volume is 6.01 mL? 2. Which of the following is an element? a. sandb. waterc. goldd. sugar 3. Differentiate heterogeneous from homogenous mixtures. 2.00 g/mL Heterogeneous mixture: parts are noticeably different; homogeneous mixture: parts are difficult to distinguish. Click the mouse button to display the answers.

5. Pretest Answers (continued) Chapter 3 4. Which of the following is NOT a step in a valid scientific method? a. developing a procedure to test your hypothesis b. drawing a conclusion without any supporting evidence c. forming a testable hypothesis d. making observations 5. Identify the tools needed to measure temperature and length. 6. True or False: All of the following units are SI units: meter, pound, and Kelvin. thermometer and ruler Click the mouse button to display the answers.

6. Pretest Answers (continued) Chapter 3 7. Density, mass, and volume are related by the equation density = mass/volume. What equation would you use to find volume if you knew the density and mass? 8. Bromine boils at a temperature of 58.63˚C. What is this temperature in Kelvin? volume = mass/density 331.78 K Click the mouse button to display the answers.

7. Interest Grabber Section 3.1 States of Matter Imagine that you have a baseball and a small packet of ketchup. 1. If you squeeze the ketchup packet, how would it change? 2. If you squeeze the baseball, how would it change? 3. What would these results tell you about the properties of solids and liquids?

8. Interest GrabberAnswers Section 3.1 1. If you squeeze the ketchup packet, how would it change? The shape of the packet would change. 2. If you squeeze the baseball, how would it change? The baseball would not change shape in any noticeable way. 3. What would these results tell you about the properties of solids and liquids? You may say that solids have a shape that doesn’t change under ordinary circumstances but that a liquid can change shape (flow) as the shape of its container changes.

9. 3.1 Solids, Liquids & Gases • Describing States of Matter: *Based on whether shapes and volumes are definite or variable • Solids= state of matter where volume and shape is definite • Liquids= state of matter where volume is definite but shape is variable • Gases= state of matter where neither volume or shape is definite • Other a. Plasma=99% of universe’s matter

10. 3.1 • Kinetic Theory= particles of matter are in constant motion 1. Kinetic Energy= energy of an object due to motion

11. 3.1 • Explaining the Behavior of Gases • Gas particles are in constant motion • Move until they collide with something • Kinetic Theory of Gases= constant motion of particles allows gas to fill container • Explaining the Behavior of Liquids • Speed of particles is slower than in gases • Particles are closer together than gases • Explaining the Behavior of Solids • Particles vibrate in a fixed location • Particles have a strong attraction to each other

12. Reading Strategy Section 3.1 Previewing a. definite shape b. definite volume c. variable shape d. variable volume

13. Interest Grabber Section 3.2 Inside a Helium Balloon A tank of compressed helium gas is often used to fill party balloons. 1. What is happening to the helium atoms inside the balloon? 2. What might happen if more helium were added to the balloon? How could adding more helium cause this result?

14. Interest GrabberAnswers Section 3.2 1. What is happening to the helium atoms inside the balloon? The atoms are constantly moving. They move in a straight line until they collide with other atoms or the inner surface of the balloon. 2. What might happen if more helium were added to the balloon? How could adding more helium cause this result? If enough helium is added to the balloon, it will burst. Accept any logical explanation.

15. 3.2 Gas Laws • Pressure= result of force distributed over an area • Derived unit of newtons/meters2 = the Pascal (Pa) • Particles colliding with the container walls produces pressure • Factors that Affect Gas Pressure: • Temperature: increase in temperature = increase in pressure (higher temp= more kinetic energy= more collisions) • Volume: reducing the volume of a gas increases pressure (increases collisions) • Number of Particles: increasing number of particles increases pressure (increases collisions) *Assuming 1/3 changes while 2/3 are constant*

16. Reading Strategy Section 3.2 Identifying Cause and Effect a., b., and c. temperature, volume, number of particles

17. 3.2 • Charles’s Law: • The volume of a gas is directly proportional to the temperature in kelvins if pressure and number of particles remain constant • V1=V2 T1 T2 3. Theorized absolute zero as temperature where gas has 0 volume (0 Kelvin)

18. Charles’s Law Figure 13A

19. 3.2 • Boyle’s Law: 1. The volume of a gas is inversely proportional to the pressure if its temperature and number of particles are constant 2. P1V1=P2V2 3. Pressure measured in Pascals (kilopascals)

20. Boyle’s Law Figure 13B

21. The Combined Gas Law Section 3.2

22. The Combined Gas Law Section 3.2

23. The Combined Gas Law Section 3.2

24. The Combined Gas Law Section 3.2

25. Interest Grabber Section 3.3 Three States of Water Water is an abundant substance on Earth. It can be found as a solid, a liquid, and as a gas called water vapor. 1. How many words can you think of to describe solid water? 2. Where is most of the liquid water on Earth found? Where is most of the water vapor found? 3. Describe a natural event you have observed when water changed from a liquid to a solid, and when water changed from a liquid to a vapor.

26. Interest GrabberAnswers Section 3.3 1. How many words can you think of to describe solid water? Answers may include forms such as ice, sleet, snow, and hail or formations such as glaciers, icebergs, and ice caps. 2. Where is most of the liquid water on Earth found? Where is most of the water vapor found? Most liquid water is found in oceans (which cover 71% of Earth’s surface). Water vapor is found in Earth’s atmosphere. 3. Describe a natural event you have observed when water changed from a liquid to a solid, and when water changed from a liquid to a vapor. Answers may include a pond freezing over or water evaporating from a puddle.

27. 3.3 Phase Changes • Phase Change= the reversible physical change that occurs when a substance changes from one state to another • Six common phase changes: • Melting • Freezing • Vaporization • Condensation • Sublimation • deposition

28. Phase Changes Figure 16

29. 3.3 B. Temperature & Phase Changes: 1. Temperature does NOT raise or lower during a phase change… it stays constant 2. Graphs showing phase changes look like stairsteps • Energy & Phase Changes • During a phase change energy is transferred between substance and surroundings • Endothermic=the substance absorbs energy • Exothermic= the substance releases energy • Heat of Fusion= amount of energy absorbed during melting

30. Heating Curve for Naphthalene Figure 16

31. Heating curve of H2O

32. Heating curve of H2O Condensation Vaporization

33. Heating curve of H2O Condensation Vaporization Melting Freezing

34. 3.3 • Melting & Freezing: 1. Melting a. Arrangement of molecules becomes more orderly during freezing and less orderly during melting b. Energy absorbed during melting helps molecules overcome their “fixed” arrangement c. After melting extra energy increases temp of substance 4. Freezing a. As energy leaves during freezing the molecules move more slowly b. Freezing occurs when molecules arrange in fixed arrangements (does not always need to be cold)

35. 3.3 • Vaporization & Condensation: • Vaporization=substance changes from a liquid to a gas, is endothermic • Heat of vaporization= amount of energy absorbed during vaporization, varies between substances • Evaporation= change from a liquid to a gas at a temperature below the boiling point • Vapor pressure= pressure created in a closed container when evaporated molecules collide with container walls, increases temp,

36. 3.3 5. Boiling a. liquid is heated until some molecules turn to a gas, these “bubbles” rise to the top of the liquid releasing the vapor b. Boiling occurs when temperature raises vapor pressure to equal atmospheric pressure • Condensation= phase change when a gas becomes a liquid • Dew on grass, a “sweating” glass • Dewpoint= temp at which condensation will happen that day/night

37. 3.3 • Sublimation & Deposition: 1. Sublimation= phase change where substance changes from solid to gas without going through liquid state a. Endothermic 2. Deposition=when a substance changes from a gas to a solid without going through the liquid state a. Exothermic b. Frost on windows

38. Reading Strategy Section 3.3 Summarizing a. liquid d. liquid e. gas f. gas b. liquid c. gas

39. Go Online Chapter 3 Data Sharing Self-grading assessment Articles on properties of matter For links on gas laws, go to www.SciLinks.org and enter the Web Code as follows: ccn-1032. For links on phases of matter, go to www.SciLinks.org and enter the Web Code as follows: ccn-1033.