Metallic Bond

Question 1

Structure of metals

Answer 1

Metal atoms are held strongly together by metallic bonding to form a giant lattice structure.

In the metal lattice, metal atoms lose their outer electrons and become positively-charged ions. The outer electrons no longer belong to any metal atom and are said to be delocalised.

The outer electrons move freely between the metal ions like a cloud of negative charge.

Hence, the metal lattice structure is described as a lattice of positive ions surrounded by a ‘sea of mobile electrons’.

Question 2

Metals are good conductors of electricity.

Answer 2

While the atoms of a metal are tightly packed, the outer electrons of the atoms can break away easily from the atoms. Thus, the outer electrons are able to move freely within the metal lattice. These mobile electrons allow metal to conduct electricity.

Question 3

Metals are good conductors of heat.

Answer 3

This is due to the movement of the mobile electrons within the metal lattice. Heat energy is transferred easily by the mobile electrons in the structure.

Question 4

Metals usually have high densities, melting and boiling points.

Answer 4

Atoms in a metal are packed tightly in layers and are held together by strong metallic bonds, and a large amount of energy is required to break these bonds.

Question 5

Metals are malleable and ductile.

Answer 5

When a force is applied to a metal, the layers of metal atoms can slide over each other through the ‘sea of electrons’.