Iron and aluminium

Question 1

Metals

Answer 1

Metals are malleable - they can be bent and shaped without breaking. This is because they consist of layers of atoms that can slide over one another when the metal is bent, hammered or pressed.

Question 2

What are metallic bonds

Answer 2

Metals form giant structures in which electrons in the outer shells of the metal atoms are free to move. The metallic bond is the force of attraction between these free electrons and metal ions. Metallic bonds are strong, so metals can maintain a regular structure and usually have high melting and boiling points.

Question 3

Metal extraction and the reactivity series

Answer 3

The method used to extract a metal from its ore depends upon the stability of its compound in the ore, which in turn depends upon the reactivity of the metal:

• The oxides of very reactive metals, such as aluminium, form stable oxides and other compounds. A lot of energy is needed to reduce them to extract the metal.
• The oxides of less reactive metals, such as iron, form less stable oxides and other compounds. Relatively little energy is needed to reduce them to extract the metal.

So, the method of extraction of a metal from its ore depends on the metal’s position in the reactivity series.

Question 4

Extracting aluminium

Answer 4

Aluminium is the most abundant metal on Earth. But it is expensive, largely because of the amount of electricity used in the extraction process.
Aluminium ore is called bauxite. The bauxite is purified to yield a white powder - aluminium oxide - from which aluminium can be extracted.