ZIMSEC O Level Combined Science Notes:Copper and its alloys
- Copper is a common element found in the earth’s crust
- It can occur as an element, as copper oxide or as sulphide ore
- In Zimbabwe:
- Sulphide copper deposits can be found on the Great Dyke near Mhangura
- Oxide and carbonate ores are mined near Chinhoyi and Umkonda mine in the lowveld
- Copper ore is smelted at Alaska mine which also receives concentrated copper ore from Mhangura
- Pure copper is not a very strong metal
- It however has several uses due to its properties:
- It is used in solar heaters, car radiators, hot water pipes and cooking pots due to itsĀ high thermal conductivity
- It is used in electrical cables, wires and electrical conducts due to itsĀ good electrical conductivity
- Ease of working means it is used to make various items such as statues and valves
- Has a bright lustre which means it is used as jewelry and for decorative purposes
- It is used to protect the underside of boats since it is resistant to the corrosiveness of sea water
- It is sonorous so it is used to make bells
Copper alloys
- Before the discovery of steel copper alloys were commonly used by people for everyday uses
- Some the alloys of copper and their past and present uses are listed in the table below
Alloy | Composition | Properties of the Alloy | Uses of the alloy |
---|---|---|---|
Brass | copper and zinc | High lustre when polished, resonant and soft | Bullet cartridges, music instruments, hot water pipes, screws and Ornaments |
Bronze | Copper and tin | hard, wear resistance, tough, sonorous | statues, medals and bells |
Nickel-silver | copper and nickel | Light, wear resistant | silver coins |
To access more topics go to the Combined Science Notes page.