2. B. Physical vs. Chemical Examples: –melting point –flammable –density –magnetic –tarnishes in air physical chemical physical chemical Physical vs. Chemical

3. A.A B.B C.C D.D Section 3-1 Section 3.1 Assessment Density is what kind of property? A.atomic B.intensive C.extensive D.dependent

4. A.A B.B C.C D.D Section 3-1 Section 3.1 Assessment What defines a gas? A.Gases have a definite volume and shape. B.Gases have a definite volume but take the shape of their container. C.Gases have no definite volume or shape. D.Gases have a definite shape but no definite volume.

5. Section 3-2 Section 3.2 Changes in Matter Define physical change and list several common physical changes. observation: orderly, direct information gathering about a phenomenon Define chemical change and list several indications that a chemical change has taken place. Apply the law of conservation of mass to chemical reactions.

6. Section 3-2 Section 3.2 Changes in Matter (cont.) Matter can undergo physical and chemical changes. physical change phase change chemical change law of conservation of mass

7. Section 3-2 Physical Changes A change that alters a substance without changing its composition is known as a physical change. physical change A phase change is a transition of matter from one state to another.phase change Examples:

8. Section 3-2 Chemical Changes A change that involves one or more substances turning into new substances is called a chemical change.chemical change changes the identity of a substance products have different properties Examples:

9. B. Physical vs. Chemical Signs of a Chemical Change –change in color or odor –formation of a gas –formation of a precipitate (solid) –change in light or heat

10. B. Physical vs. Chemical Examples: –rusting iron –dissolving in water –burning a log –melting ice –grinding spices chemical physical chemical physical Physical vs. Chemical

11. B. Physical vs. Chemical Reaction occurs when one or more substances are changed into new substances. Reactants- stuff you start with; elements or compounds Products- What you make products have NEW PROPERTIES Yields Arrow separates reactants and products

12. Section 3-2 Conservation of Mass The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction, it is conserved.law of conservation of mass The mass of the reactants equals the mass of the products. mass reactants = mass products

13. Example: When 4 grams of hydrogen gas are combined with 32 grams of oxygen gas, water is created, with no remaining gas. What mass of water is formed?

14. Example 2: Some potassium oxide was placed in 9 grams of water and 112 grams of potassium hydroxide were made. If there are no remaining reactants, what mass of potassium oxide was used?

15. A.A B.B C.C D.D Section 3-2 Section 3.2 Assessment When one substances turns into another, what kind of change has taken place? A.chemical reaction B.physical reaction C.extensive reaction D.nuclear reaction

16. A.A B.B C.C D.D Section 3-2 Section 3.2 Assessment The law of conservation of mass states that: A.Matter can be created and destroyed. B.Matter can be created but not destroyed. C.The products of a reaction always have a greater mass than the reactants. D.The products of a reaction must have the same mass as the reactants.

17. Homework: complete both sides of the worksheet. Have a data and results table ready for tomorrow’s activity Quiz Thursday vocab Quiz Friday sections 3.1 and 3.2