Chemistry Day 5. Friday, August 31 st Tuesday, September 4 th, 2018

Transcription

1 Chemistry Day 5 Friday, August 31 st Tuesday, September 4 th, 2018

2 Do-Now Title: BrainPOP: States of Matter 1. Write down today s FLT 2. List two examples of gases 3. List two examples of things that are liquid 4. What do you think the difference between a liquid and a gas is? 5. How can you turn water into ice, and ice into water? What do you need to do? 6. Underneath your do-now, write brainpop practice and number Turn in your lab packet when finished Finished? Take out your planner and table of contents.

3 Chapter 13 Notes Intro

4 Identifying Substances Matter that has a uniform and definite composition is called a substance Ex: Gold and Copper

5 States of Matter 3 states of matter: solid, liquid, and gas. All matter is made up of tiny particles

6 States of Matter Solid: dopamine Definite shape Definite volume. The particles in a solid are packed tightly together, have an orderly arrangement, and vibrate in place

7 Liquid: States of Matter Indefinite shape & definite volume. Flows. Liquids are not easily compressed The particles in a liquid have enough energy to move freely in random directions, but remain close to each other.

8 Gas: States of Matter Indefinite shape and volume (takes the shape and volume of its container) It s easily compressed because there s so much empty space. Gas particles move at high speeds and randomly.

9 Pair-Share-Respond 1. What are the 3 states of matter? 2. Describe each of the three states in terms of their shape and volume. 3. Describe each of the three states in terms of their molecules.

10 Ch. 13 Part A: The Nature of Gases

11 Kinetic Energy

12 Kinetic Energy Kinetic energy: Energy an object has because of its motion Think about it: To accelerate an object, we must apply a force. But once applied, energy has been transferred to the moving object. Kinetic energy is simply the energy an object has because of its motion

13 Kinetic Energy

14 Kinetic Energy All matter consists of tiny particles that are in constant motion. In a gas, these particles are molecules or atoms

15 Kinetic Energy & Gases In the 1800s, scientists were studying gases. How could they describe the properties of substances with no fixed shape or volume?

16 Kinetic Theory Applied to Gases 1. Gases are made of molecules. These are tiny spheres with insignificant volume 2. Molecules are in constant, random motion. They have kinetic energy. 3. Collisions are perfectly elastic. When molecules collide, they do not lose kinetic energy

17 Behavior of Gases

18 Properties of Gases The molecules in gases are in constant motion This allows gases to expand until it fills its container

19 Gas and Temperature As temperature increases, molecules move faster As temperature decreases, molecules move slower Avg KE is directly proportional to temperature NOTE: At absolute zero (Kelvin), there is no movement of particles.

20 Gas Pressure

21 Gas Pressure Pressure is defined as force per unit area For example, a high heel shoe exerts a greater pressure than a normal shoe due to the smaller area of contact Larger shoes spread out the force over a greater area

22 Gas Pressure Gas particles exert pressure when they collide with the walls of their container Individual gas molecules exert a minimal pressure Gas pressure is caused by collisions of many particles against objects

23 Air is a mixture of gases Air Pressure

24 Air Pressure Because air particles are in constant motion, they exert pressure. We call this pressure atmospheric pressure or air pressure

25 Gas Pressure

26 Atmospheric Pressure Atmospheric pressure = pressure due to collisions by air molecules. Pressure decreases with increasing altitudes

27 Barometer Barometer measures atmospheric pressure

28 Pair-Share-Respond 1. Define or describe kinetic energy 2. Identify the three parts of the kinetic molecular theory applied to gases 3. What happens to kinetic energy as temperature increases? 4. What is atmospheric pressure?

29 Measurements

30 Measurements In chemistry, we often use measurements at standard temperature and pressure (STP) Standard temperature and pressure (STP) = 273 K (0 C) and 1 atm pressure

31 Measurements In chemistry, we often use different units for the same measurement Ex/ temperature can be measured in Fahrenheit, Celsius, or Kelvin units 0 C = 32 CF = 273 K Consequently, we need to be able to convert between these units

32 Converting Between Units of Pressure Units of Pressure: Pascal (Pa) SI unit Kilopascal (kpa) Millimeters of mercury (mmhg) Atmospheres (atm) Torr

33 Converting Between Units of Pressure Conversion Factors for Pressure: 1atm = 760mmHg = 760torr = 101,325Pa = kPa

34 Converting Between Units of Pressure First: Write what you start with Second: Draw a conversion factor (ratio) this is called dimensional analysis New Units Given Number and units Given Units

35 Converting Between Units of Pressure Ex/ Convert atm to mm Hg Recall:1atm = 760mmHg = 760torr = 101,325Pa = kPa Given Number and units

36 Now you try! Convert kpa to atm Convert 9.1 torr to mm Hg

37 Chemistry Day 6 Wednesday, September 5 th Thursday, September 6 th, 2018

38 Do-Now Title: Ch. 13/14 CN Part B 1. Write down today s FLT 2. List and briefly describe the three states of matter. 3. Convert kpa to atm. Show all work and units. 4. Convert 9.1 atm to mmhg. Show all work and units. 5. We will take notes under our do-now. Draw or fold your column for cornell notes. Finished? Take out your planner and table of contents.

39 FLT I will be able to describe the properties of liquids and solids by completing Ch. 13/14 Notes B Standard HS-PS1-4: Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.

40 Recall

41 States of Matter 3 states of matter: solid, liquid, and gas. All matter is made up of tiny particles

42 The Nature of Liquids

43 The Nature of Liquids Liquids have an indefinite shape and a definite volume The molecules in liquids are always moving, so they have kinetic energy This allows them to take the shape of their container just like gases

44 Gas Particles vs. Liquid Particles Gas particles are different than liquid particles: 1. Liquid particles attract each other, but gas particles do not.

45 Gas Particles vs. Liquid Particles Gas particles are different than liquid particles: 2. Because of their attraction, liquid particles are closer together. Liquids have a definite volume

46 Gas Particles vs. Liquid Particles Gas particles are different than liquid particles: 3. Liquids are more dense than gases. Liquid molecules are more closely packed together.

47 Changing State Liquids can turn into gases and vice versa

48 What s happening? Vaporization = liquid à gas/vapor

49 Evaporation Evaporation = vaporization at the surface of a liquid that is not boiling

50 Evaporation Liquids evaporate faster when heated AVG KE increases Liquid particles are able to move faster and separate

51 Vapor Pressure Vapor Pressure = pressure exerted by a vapor over a liquid Water vapor collects above the liquid and exerts pressure due to collisions

52 Boiling Point Remember: liquids are attracted to each other. They LIKE being close together. Adding heat adds energy so that particles can overcome the attractive forces and enter the gaseous state.

53 Boiling Point Boiling Point (BP) = temperature at which the VP of the liquid is equal to the external pressure on the liquid. Molecules even at the bottom of the liquid have enough energy to vaporize, so they rise to the surface

54 Pair-Share-Respond 1. Identify two ways that liquids differ from gases 2. Distinguish between the terms vaporization and evaporation 3. Why does heating increase the rate of evaporation? 4. Define the term vapor pressure

55 The Nature of Solids

56 The Nature of Solids Solids have a definite shape and volume Solids à orderly arrangement, vibrate in fixed positions, and do not flow

57 Change of State Solids can turn into liquids and vice versa

58 Melting Point Melting point (MP) = temp at which solid à liquid = the same temp as the freezing point (liquid à solid) At the melting point, the vibrations are strong enough to overcome the attractions holding them in fixed positions.

59 Crystalline Structure Solid structures = Most are crystalline In a crystal the particles are arranged in an orderly, repeating, three-dimensional pattern called a crystal lattice.

60 Crystalline Structure Are ALL solids crystalline? Some solids may be amorphous. Amorphous solids = lack uniform, geometric arrangement

61 Allotropes Allotropes = Some solid substances can exist in more than one form Ex. Allotropes of carbon (diamonds and graphite) Different structures give allotropes different properties

62 Pair-Share-Respond 1. Describe how you would draw a solid 2. Distinguish between the terms crystalline structure and amorphous solids 3. What are allotropes?

63 Chemistry Day 7 Friday, September 7 th Monday, September 10 th, 2018

64 Do-Now Title: Ch. 13/14 Notes C 1. Write down today s FLT 2. List the three states of matter and list an example for each 3. List two similarities between gases and liquids 4. is the change of a liquid into a vapor 5. Explain why changing the temperature can help speed up the process of evaporation. 6. We will take notes under our do-now. Draw or fold your column for cornell notes. Finished? Take out your planner and table of contents.

65 FLT I will be able to identify the temperature and pressure conditions for states of matter by completing Ch. 13/14 Notes C Standard HS-PS1-4: Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.

66 Changes of State

67 Changes of State: Draw This Sublimation Melting Vaporization Freezing Condensation KE Increases

68 Changes of State Sublimation = Direct change from solid to vapor (without passing through liquid phase)

69 Changes of State Sublimation can occur because solids and liquids have vapor pressure Sublimation occurs in solids with vapor pressures that exceed atmospheric pressure at or near room temperature.

70 Sublimation Applications: Freeze-dried goods, coolants, and air fresheners.

71

72 Phase Diagrams Phase Diagram = Diagram that shows the relationships among solid, liquid, and vapor states of a substance

73 Phase Diagrams Shows the temperature and pressure at which substances exist at each state You can locate the normal melting point, normal boiling point, triple point, and critical point on the diagram

74 Triple Point

75 Phase Diagrams Triple Point = Set of conditions at which the three phases exist in equilibrium At the critical point, the physical properties of the liquid and gaseous states are identical

76

77 That s it J

78 States of Matter Inquiry Mini- Lab