Metallic Bonding

Question 1

Common Properties of Metals

Answer 1

1. Lustrous
2. Malleable
3. Ductile
4. Conductors of heat
5. Conductors of electricity
6. High density
7. Generally high melting points
8. Hard/durable

Question 2

Electronegativity of Metals

Answer 2

Metals tend to be low in electronegativity as will lose outer shell electrons in bonding, becoming a positively charged cation to produce more stable electron configurations.
Metals have metallic lattice structures made up of atoms and a sea of free moving electrons that flows between the cations, known as delocalised electrons.

Question 3

Lusture of Metallic Crystals

Answer 3

Lustrous appearance is due to the free moving electrons in the lattice reflecting light back into the eye, causing the metal to look shiny.

Question 4

Malleability and Ductility

Answer 4

Metals are malleable and ductile due to the non-directional nature of metallic bonds. When a force is placed onto the metal, the free moving electrons allows the layers of cations to move past each other without disrupting the attractive force. Therefore, the nature of the metal does not change when it is hammered or pulled into strings.

Question 5

Electrical Conductivity

Answer 5

Metals are good conductors of electricity as the free moving electrons allow for a flow of charge known as an electric current. The electric field causes one end of the metal to be positive and the other to be negative as electricity flows through.

Question 6

Heat Conductivity

Answer 6

Metals are good conductors of heat as the electrons gain kinetic energy in areas of high temperatures and can efficiently move to transfer the heat to colder parts of the metal lattice due to free movement. Heat naturally flows from areas of high to low temperature. Heat/kinetic energy causes electrons to move faster and bump against each other to transfer heat throughout the metal.

Question 7

Density

Answer 7

Metals tend to be high density as the metallic lattices are closely packed together.

Question 8

Melting Points and Hardness

Answer 8

Metals have generally high melting points and are known for being durable. This indicates that metallic bonding is quite strong however it is not as strong as covalent or ionic bonding. Melting points and durability increases as the number of outer shell electrons increases as there is ultimately a greater attractive force between cations and free moving electrons.

Question 9

Alloys and Properties of Alloys

Answer 9

Alloys are, for example, generally harder than pure metals. They are made up of atoms of different sizes, rather than being uniform. This means that the layers of atoms cannot slide over each other easily, making the whole alloy much stronger than any of the pure metals that the alloy contains in isolation.