Diamond and graphite

Question 1

What is meant by an allotrope?

Answer 1

Different structural forms of the same element in the same physicial state

Question 2

In terms of carbon atoms and structure discuss the differences between diamond and graphite

Answer 2

• Diamond is covalently bonded to 4 other carbon atoms
  Forms a regular 3D pattern

Graphite- bonded to 3 carbon atoms arranged in hexagons
Forms large flat sheets forming layers

Question 3

can graphite conduct electricity and heat, If so how

Answer 3

Each carbon atom in graphite has 1 free delocalised electron meaning the electron is free to move and carry an electrical current

Question 4

What are the properties of diamond?

Answer 4

High melting and boiling point

Hard

Doesn’t conduct electricity

Question 5

Why can graphite be used as lubricant?

Answer 5

Carbon atoms are arranged in layers

The forces between the layers are weak intermolecular forces.

This means not much energy is needed to break, so layers slide over each other easily.

Question 6

What are the properties of graphite?

Answer 6

High melting and boiling point

Soft and brittle

Good conductor of heat and electricity

Question 7

Does diamond or graphite have a higher melting point?

Answer 7

Diamond has a higher melting point - forms a continuous lattice where all atoms are held together by strong covalent bonds.

Graphite includes weak intermolecular forces, which require much less energy to break.