5. Watch the first video: Ch3_1_c_09_10Ancient_Philosophy_About_the_Elements.asf

7. Watch the second video:Ch3_1a_09_10.asx

8. Watch the third video:Ch3_1b_09_10.asx

11. The Law of Conservation of Mass Note: The mass of the products in a chemical reaction must be the same as the mass of the reactants. Burned paper is not destroyed, it chemically combines with oxygen and forms carbon monoxide or, in most cases, carbon dioxide. Low heat, like car engines – carbon monoxide. High heat, like crematoriums – carbon dioxide.

12. Watch the fourth video: Conservation of Mass: Heating Cu and S.avi

14. The Law of Definite Proportions

16. The Law of Multiple Proportions