1. Unit 2- Materials: Structure and Uses Section 2. A – Why we use what we do

2. Do Now Read pages. 108-109 What kind of coin would you like to have?

3. Objectives 1. SWBAT define properties and changes. 2. SWBAT distinguish between physical and chemical changes and classify examples of each. 3. SWBAT differentiate between metals, non metals, and metalloids and their locations on the period table. Wkst – U2A1, HW pg 130 (1-6)

4. 2.A.1 Properties make the difference What are some materials people of the past have used as currency? What makes a material suitable or useable to produce coins? How important is appearance or cost?

5. Physical Properties Characteristics that distinguish elements from other things Ex. Color, density, odor… Can be observed without altering chemical structure

6. Chemical Property Describes how the element reacts with other elements or substances

7. Chemical vs. Physical Changes Chemical ChangePhysical Change -substance changes into one or more NEW substances EX- -Appearance can change although chemical structure remains intact EX-

8. Example 1 Iron RUSTING: Observing a chemical change can often mean the formation of a gas or solid Thermal energy can be given off or absorbed

9. p.111- Developing Skills Consider the statement: Copper compounds are often blue in color. Does this statement describe a physical or chemical property? Why?

10. p. 111 – Developing Skills Consider this statement: Oxygen gas supports the burning of wood. Does this statement refer to the physical or chemical property of oxygen gas? Explain.

11. Answer Burning or combustion of wood- involves a chemical reaction Wood and oxygen (reactants) change into ash, carbon dioxide and water vapor.

12. Do Now List at least one chemical property and one physical property

13. Objectives 1. SWBAT distinguish between physical and chemical changes and classify examples of each.

14. Think-Pair-Share Pg 112 #1-9

15. Complete WKST U2A1 HW

16. A.3 Properties Matter: Designing the Penny 1. Cost A. Cost of the production of the penny must be matched by it’s face value ($0.01) B. Early 1980s Copper became too expensive and Zinc replaced it C. In 1943, during WWII, Zinc plated steel pennies (quickly corroded)

18. A.3 Properties Matter: Designing the Penny 2. Solution Post 1982 pennies – 97.5% Zinc Copper coating a Zinc Core

19. A.4. Chemical Elements Elements are classified in three major groups: Metals Nonmetals Metalloids Take out your PTOE to color in the different sections

20. Periodic Trends

21. Transition Metals

22. Physical Properties of Metals Malleability Ductility Luster Heat conductors and electrical conductors Typically reacts with acids Ex. Iron (Fe), tin (Sn), zinc (Zn), and copper (Cu)

23. Properties of Nonmetals Dull in appearance Brittle Do not conduct electricity Ex. Carbon (C) and Oxygen (O)

24. Metalloids Properties of metals and nonmetals Ex. Silicon (Si) and Germanium (Ge)

25. Do Now List the following as a chemical or physical change 1. A piece of wood burns to form ash. 2. Water evaporates into steam. 3. A piece of cork is cut in half. 4. A bicycle chain rusts. 5. Food is digested in the stomach. 6. Water is absorbed by a paper towel. 7. A change in color

26. Objectives 1. SWBAT review physical and chemical changes 2. SWBAT identify trends in the periodic table.

27. Objectives SWBAT identify properties of metals, nonmetals, or metalloids SWBAT create their own trends in the periodic table.

28. Periodic Table Used to organize elements based on their properties

29. Dimitri Mendeleev Created a periodic table of elements based on: 1. Atomic Weights 2. “Combining Capacity”

31. Now you Try Turn to page 119 and follow steps #1-6 Try to create your own periodic table based on several different properties

32. Transition Elements/Metals

33. Periodic Trends Periods: horizontal rows Groups/Families: vertical columns

34. Trends in Periodic Families Alkali Metal Family: Group 1 Highly reactive Metals (cations) Noble Gas Family: Group 18 Unreactive (chemically inert) elements Halogen Family: Group 17 Highly reactive (anions)