Material properties

Question 1

Define covalent

Answer 1

A covalent substance is a molecule containing one or more covalent bonds (shared pairs of electrons)

Question 2

What is the structure of diamond?

Answer 2

Diamond has a giant covalent structure which:
- Each carbon atom is joined to four other carbon atoms by covalent bonds
- The carbon atoms have a regular lattice arrangement
- There are no free electrons

Question 3

What are the properties for diamond?

Answer 3

Makes diamond very hard, useful for cutting tools, such as a diamond-tipped glass cutters and oil rig drills

Question 4

What is the structure for graphite?

Answer 4

Graphite has a giant covalent structure which:
- Each carbon atom is joined to three other carbon atoms by covalent bonds
- The carbon atoms form layers with a hexagonal arrangement of atoms
- The layers have weak forces between them
- Each carbon atom has one non-bonded outer electron, which becomes delocalised

Question 5

Define delocalised

Answer 5

Electrons that are not associated with a particular atom eg in metal outer electrons can be free top move through the solid

Question 6

What are the properties of graphite?

Answer 6

Useful for electrode in batteries and for electrolysis. Useful as lubricant

Question 7

What is the structure of graphene?

Answer 7

It’s structure resembles a single layer of graphite.

Question 8

What are the properties of graphene?

Answer 8

• Has a very high melting point and is very strong because of its large regular arrangement of carbon atoms joined by covalent bonds.
• Like graphite, graphene conducts electricity well because it has a delocalised electrons that are free to move through it’s structure

Question 9

What are fullerenes?

Answer 9

Fullerenes are forms of carbon and include nanotubes and bucky balls