Warm-Up 9/9. 1. Define the term matter. 2. Name something in this room that is not matter.

Transcription

1 Warm-Up 9/9 1. Define the term matter. 2. Name something in this room that is not matter.

2 Warm-Up 9/16 1. List the three most important rules of lab safety. 2. Would you classify jello as a solid or a liquid? Justify your choice.

3 Today s Learning Targets Power Standard: Students understand that physical and chemical properties depend on the ways in which different atoms combine.

4 Today s Learning Targets 1. I can list examples of physical properties. 2. I can describe the physical characteristics and particle arrangement in solids, liquids, and gases. 3. I can explain observable changes in physical properties and temperature during changes of state.

5 A. Properties of Matter 1. Matter- anything that has mass and volume. 2. Mass - a measure of the amount of matter in a substance 3. Substance (pure substance) - matter with uniform and definite composition 4. Physical Change A change that does not alter the chemical composition of the substance

6 B. Physical Properties Include Mass Weight Color Density Melting point Etc.

7 B. Physical Properties Can be observed without changing the chemical composition of the substance. Example List 3 physical properties of water.

8 Warm-Up 9/14 1. State 2 physical properties of sucrose (table sugar). 2. Give an example of a physical change that water can undergo.

9 Today s Learning Targets Power Standard: Students understand that physical and chemical properties depend on the ways in which different atoms combine.

10 Today s Learning Targets 1. I can describe the physical characteristics and particle arrangement in solids, liquids, and gases. 2. I can explain observable changes in physical properties and temperature during changes of state. 3. I can classify mixtures as either homogeneous or heterogeneous.

11 B. States of Matter 1. Solid - has definite shape and volume; particles tightly packed in fixed positions 2. Liquid - indefinite shape, definite volume; particles tightly packed, but not in fixed positions (slide past one another -flow) 3. Gas - indefinite shape and volume; particles far apart; compressible

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13 Animation States of Matter Animation Are there other states of matter?

14 D. Phase Changes 1. Temperature Measures the KE of particles of matter. Always constant during a phase change. (Yes, really!)

15 2. Names of Phase Changes a. Solid/Liquid Melting or Freezing b. Liquid/Gas Boiling or Condensing c. Solid/Gas Sublimation or Deposition

16 D. Heating/Cooling Curve Animation

17 D. Heating/Cooling Curve Copy this heating curve onto your notes. Label where melting and boiling occur.

18 Warm-Up 9/16 Assume the heating curve represents substance X that starts as a solid below its melting point and is heated uniformly. 1. Identify the process that takes place during line segment DE of the heating curve 2. Identify a line segment in which the average kinetic energy is increasing. 3. Using "o" to represent particles of substance X, draw at least five particles as they would appear in the substance at point F. 4. Describe, in terms of particle behavior or energy, what is happening to substance X during line segment BC.

19 Today s Learning Targets 1. I can state and explain common methods for separating mixtures. 2. I can state that atoms of different elements combine in fixed ratios to form compounds, which have different properties from their component elements. 3. I can state that mixtures contain more than one element and/or compound that are not chemically bonded together and so retain their individual properties. 4. I can classify mixtures as homogeneous or heterogeneous. 5. I can explain that elements are the basic building blocks of matter and discuss how they can physically mix or chemically combine.

20 E. Physical Changes Alter the material without changing the chemical composition of it. 1. Examples - cutting, bending, melting, freezing 2. Terms - tear, smash, crush, boil, freeze, dissolve, melt, condense, grind, etc.

21 II. Mixtures

22 Key Definitions Mixture--two or more substances physically, not chemically, combined. Heterogeneous mixture Contains more than one phase Ex - oil & water, chicken noodle soup

23 Key Definitions Homogeneous mixture Only one phase Ex - salt water, apple juice Solution--a homogeneous mixture;

24 Key Definitions Phase part of a mixture with uniform composition and properties

25 Question How do you know if a sample is a mixture or a substance? Answer: Mixtures have variable composition they come in different formulations Substances have definite composition they only come in one chemical form

26 Classifying mixtures 1. Can mixtures always be identified by sight? Chicken noodle soup? Coin jar? (yes) Air? Gasoline? Soda? (no) 2. Variable Composition Different samples have different ratios of ingredients (i.e. - iced tea) Indication of a mixture

27 A. Examples of Mixtures Identify as heterogeneous or homogeneous Air Tap water Blood Apple Juice Soap Brine (salt water)

28 Question How might you separate a mixture of sulfur and iron? Examine properties and look for a difference Magnetism

29 B. Separating Mixtures 1. Can be done by physical means, without chemistry. 2. Common ways mixtures are separated include distillation, filtration, evaporation, decanting, chromatography

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31 III. Elements & Compounds

32 Key Definitions Element The simplest form of matter that exists under normal laboratory conditions Ex - hydrogen, sulfur, gold Another element song

33 Key Definitions Compounds Chemically bonded combinations of elements in specific ratios Chemical Symbol One or two letter designation for an element. Chemical Formula Shows the ratio of atoms in the simplest unit of a substance

34 Elements & Symbols There are 90 naturally occurring elements Element symbols come from the Latin names for elements Examples: Carbon (C), Iron (Fe) Forging Elements The Elements Song

35 Warm-Up 9/20 1. What are the 2 classes of mixtures? 2. Which has only 1 phase? 3. What is a physical property you could use to separate a mixture of sand and salt? 4. Name a fundamental difference between a compound and a mixture.

36 Today s Learning Targets Power Standard: Students understand that physical and chemical properties depend on the ways in which different atoms combine.

37 Today s Learning Targets 1. I can state that atoms of different elements combine in fixed ratios to form compounds, which have different properties from their component elements. 2. I can give examples of chemical compounds. 3. I can suggest experimental techniques to distinguish between mixtures, elements, and compounds.

38 Compounds Definite and Uniform composition Examples Sodium chloride Sucrose Sodium hydrogen carbonate Representing (formulas) NaCl C 12 H 22 O 11 NaHCO 3

39 Distinguishing between compounds & elements Elements cannot be broken down by chemical means Compounds can be separated into simpler substances by chemical change Properties of compounds differ from the properties of their elements.

40 Distinguishing between Mixtures & Compounds Can be difficult for homogeneous mixtures Ask yourself if it can have variable composition from sample to sample. If so, it s a mixture. 1. Examples: Gasoline? Exists in different grades, may contain ethanol = mixture Milk? Contains different amounts of fat = mixture Water? Always H 2 O = compound

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42 IV. Chemical Change

43 IV. Chemical Reactions 1. Chemical Reaction - results in new substances 2. Product new substances formed in a reaction 3. Reactant - starting substances 4. Chemical Property describes the chemical changes a substance can undergo

44 B. Chemical Change Signs of a chemical reaction Odor, color change, change in temp, production of a gas or solid (precipitate - ppt) Chemical changes cannot be easily reversed! Terms Spoiling, rotting, burning, corroding, oxidizing, etc. Chemical vs. Physical Change

45 Chemical properties Examples - iron can rust; plastic cannot hydrogen is explosive; helium is not

46 C. Conservation of Mass Law of Conservation of Mass Mass of reactants = mass of products (Matter cannot be created or destroyed.) Example 2.5 g Na g Cl g NaCl