Giant covalent molecules Flashcards
Give five examples of giant covalent structures.
- silicon dioxide
- diamond
- graphite
- graphenes
- fullerenes
Which two elements make up silicon dioxide?
- Silicon
- Oxygen
Which giant covalent structure is shown here?
Silicon dioxide
Why are giant covalent structures solid at room temperature?
- They have high melting points and boiling points
- Large amounts of energy are needed to break strong covalent bonds between the molecules
Which element makes up diamond and graphite?
Carbon
Which giant covalent structure is shown in this diagram?
Diamond
How many carbon atoms are joined to each carbon atom in diamond?
Four
Why can’t diamond conduct electricity?
There are no free electrons
Why is diamond commonly used in cutting tools?
- Diamond is very hard
- Because carbon atoms are held together by very strong covalent bonds
Which giant covalent structure is shown here?
Graphite
In graphite, how many covalent bonds does each carbon atom form?
Three
Why is graphite slippery?
There are weak forces between the layers
The layers can slide over each other
Why can graphite conduct electricity?
Graphite has delocalised electrons
Delocalised electrons can move between the layers, carrying charge
What is graphene?
A single layer of graphite
What are fullerenes?
Molecules of carbon with a hollow shape
Name this giant covalent structure.
Buckminsterfullerene
Name this giant covalent structure.
Nanotubes
