1. Elements from Chapter 1 Section 4

2. I. Gold and Density A. Gold can be separated from a mixture because of its density 1. Gold 19.3 g/cm 3 2. Pyrite (fools gold) 5.0 g/cm 3

3. II. Copper and Electrolysis A. most elements are usually found as compounds B. Ore: any rock containing a metal or other useful element C. To isolate an element from a compound, a chemical reaction must take place

4. D. Electrolysis (“electric cutting”) 1. Used to break down certain compounds Ex. CuCl 2 a. Copper compound is dissolved to form a solution b. Pass an electric current through the solution c. Copper is deposited on one electrode (-) d. Chlorine gas bubbles at the other electrode (+)

5. III. Iron and Blast Furnace A. Iron (Fe) is found as an ore in the form of a compound (usually bound to oxygen) B. Add a carbon (C) source: coke C. Iron is separated and CO 2 (gas) is given off D. Iron can be combined with other elements to produce alloys