Metals and their uses

Rocks which contain enough of a metal or a metal compound to make it worth extracting are called ORES
Mining ores often involve digging up large amounts of rocks. The ore may need to be concentrated before the metal is extracted.
1. This process can produce large amounts of waste and may have major impacts on the environment
2. Metals are usually found in the earths crust: Combined with another element (e.g.. Oxygen)
A few metals (low in the reactivity series) -> Such as Gold are found in the Earth as the metal
1. Gold can be separated from rocks by physical methods -> HOWEVER most metals are found as compounds SO metals have to be extracted by chemical reactions
Metals can be extracted from compounds by displacement (using a more reactive element) <e.g..> Metals which are less reactive than carbon can therefore be extracted from their oxides by heating carbon
1. A metal higher up in the reactivity series will displace any metals lower in the series from their compounds. The reaction is called a displacement reaction
2. A reduction reaction can take place as carbon removes the oxygen from the oxide ---> To produce the metal
EXAMPLE 2Fe2O3 + 3C -> 4Fe =3CO2 Iron oxide+Carbon ->Iron + CO2

Zusammenfassung der Ressource

	Erstellt von anisah_2.m vor mehr als 9 Jahre