Separating metals from metal oxides

Question 1

example of oxidation

Answer 1

Lots of common metals like iron, and aluminium, react with oxygen to form oxides. This process is an example of oxidation. These oxides are often the ores that the metals need to be extracted from.

Question 2

What is called a reduction reaction ?

Answer 2

A reaction that separates a metal from its oxide is called a reduction reaction

Question 3

Formation of Metal Ore

Answer 3

Oxidation = gain of oxygen
E.g. magnesium is oxidised to make magnesium oxide

Big 2 Mg + 02 -> big 2 MgO

Question 4

Extraction of Metal

Answer 4

Reduction = loss of oxygen
e.g. copper oxide is reduced to copper
Big 2 CuO + C -> big 2 Cu + CO2

Question 5

How can some metals be extracted from their ores chemically..

What occurs in this reaction ?

Answer 5

by reduction using carbon.
In this reaction, the ore is reduced as oxygen is removed from it, and carbon gains oxygen so is oxidised.

For example : Big 2 Fe2O3 + Big 3 C -> BIG 4 + Big 3 CO2

Question 6

The position of the metals in the reactivity series determines ..

Answer 6

whether it can be extracted by reduction with carbon

Question 7

Reactivity series and how its extracted

Answer 7

K, Na, Li, Ca, Mg
Extracted using electrolysis

Carbon

Zinc
Iron
Copper
Extracted by reduction using carbon

Question 8

metals and how its extracted

Answer 8

• Metals higher than carbon is the reactivity series have to be extracted using electrolysis which is expensive
• Metals below carbon in the reactivity series can be extracted by reduction using carbon, For example : iron oxide is reduced in a blast furnace to make iron
• This is because carbon can only take the oxygen away from metals which are less reactive than carbon itself is

Question 9

Some metals are so unreactive they are ..

Answer 9

in earth as the metal itself
Example : Gold mined as its elemental form