The properties of copper allow it to be used in a wide variety. The United States is a major world supplier of this essential metal.
Copper's properties:
* second highest electrical conductivity (silver is first)
* low cost
* corrosion resistant
* ability to be drawn easily into thin wires (ductile)
The US is a major world supplier of copper ore. (Canada, Chile, Peru, and Zambia have significant supplies.)
How is it determined whether profit can be earned by mining a particular metallic ore at a certain site?
* the metal's supply-demand status
* type of mining and processing needed to obtain the metal
* amount of useful ore at the site
* distance of the mine from metal refining facility and markets
* percent of metal in the ore
p. 136-137: 1-3 TOGETHER.
D.2 Evaluating an Ore
How do geologists know how much copper or other metal is present in a particular ore?
The compound's formula indicates the number of atoms of each element in the substance.
Ex: chalcocite Cu2S
This tells us that for every one SULFUR atom, there are 2 COPPER atoms.
The percent of metal in an ore helps determine whether a particular deposit is worth mining.
What if we want to find the percent of Cu in Cu2S?
% Cu = mass of Cu X 100 =
molar mass of Cu2S
= 2(63.5)
2(63.5) + 32
= 127.1 g Cu X 100 =
159.2 g Cu2S
= 79.8% Cu
If we calculated sulfur the same way, we would find that Cu2S is 20% sulfur. (Why?)
Now, what if just 5.0% of the ore is Cu2S? That means that 5 g of 100g will have Cu2S. How much of this ore will be copper?
5.0 g Cu2S X .7984 = 4.0 g Cu
p. 138-139: 1-3
Questions? Comments??
Amanda Noland