Chapter 1 – Lesson 4 Elements from the Earth METALS!

Gold Rush & Density Real gold – made of element gold (Ag) Fool’s gold (pyrite) – made of iron & sulfur Density of gold is 19.3 g/cm 3 ▫More or less dense than water? ▫Float or sink? High density can be used to separate from other material ▫More dense than fool’s gold, sand, and dirt

Panning Mix gold, sand, dirt, and water in a pan ▫Swirl around and pour out  What sinks and what gets poured out?! Repeat many times until only gold dust is left! Is density of gold a characteristic property?

Copper & Electrolysis Ore = rock that contains a metal or other economically useful material. Copper is found in ores ▫When an electric current is passed through a solution of a copper compound, a chemical change will occur that separates copper and other elements. Electrolysis = process by which an electric current breaks chemical bonds. Electrode = metal strip used in electrolysis

Iron Iron is found in ores. Iron ores & source of carbon are placed into hot fire ▫Iron is released ▫When heated, carbon reacts with oxygen in the ore  LEAVES IRON BEHIND! Iron makes steel – important process! ***ORES VS. NATIVE METALS (mixed vs. pure)